A handbook of systematic botany (part 3 of 4)

A handbook of systematic botany (part 3 of 4)

Order 5. =Eriocaulaceæ.= The “Compositæ among Monocotyledons,” a tropical order. The flowers are borne in a capitulum surrounded by an involucre, very similar to that of the Compositæ. The flowers are very small, unisexual, ♂ and ♀ often mixed indiscriminately in the same capitulum; they have the usual pentacyclic structure; the leaves of the inner perianth are often connate and more membranous than the outer; in some the outer series of stamens are suppressed; in each of the 3 loculi is one pendulous ovule. Capsule. The leaves are generally radical and grass-like.--335 species; Eriocaulon, Paepalanthus, etc., E. septangulare on the west coast of Scotland, and Ireland, and in North America.

Order 6. =Restiaceæ.= A small, especially S. African and S. Australian, xerophilous order (about 235 species), which is quite similar in habit to the Juncaceæ and Cyperaceæ. The leaves are often reduced to sheaths. The flowers are diœcious, the perianth as in Juncus, but the outer series of stamens suppressed. The ovary and fruit as in Eriocaulaceæ; the ovary, however, may be unilocular, and the fruit a nut. Restio, etc.

Order 7. =Centrolepidaceæ.= These are the most reduced plants in the family; small grass- or rush-like herbs. The flowers are very small, naked. Stamens 1–2, carpels 1–∞. 32 species. Australia.--Centrolepis (flowers generally ☿ with 1 stamen and 2–∞ carpels).

Family 5. =Liliifloræ.=

The flower is constructed on the general monocotyledonous type, with 5 alternating, 3-merous whorls (Fig. 278), but exceptions are found as in the Iridaceæ (Fig. 279) by the suppression of the inner whorl of stamens; in a few the position in relation to the bract differs from that represented in Fig. 278, and in some instead of the trimerous, di- or tetramerous flowers are found (e.g. Majanthemum, Paris). Flowers generally regular, hermaphrodite, with simple, petaloid, coloured perianth (except, for example, Bromeliaceæ); ovary trilocular, generally with 2 ovules or 2 rows of ovules in the inner angle of each loculus (Fig. 304 C, D). Endosperm always present.--A very natural family, of which some divisions in part overlap each other. The habit varies; the leaves are however long, entire, with parallel venation, except in Dioscoreaceæ (Fig. 313).

In the first orders of this family the flowers are hypogynous, and in the first of all the styles are free, and the capsule dehisces septicidally; in the following the flowers are epigynous and in some reduced in number or unisexual; capsule with loculicidal dehiscence, or a berry.

HYPOGYNOUS flowers: Colchicaceæ, Liliaceæ, Convallariaceæ, Bromeliaceæ (in part).

EPIGYNOUS flowers: Amaryllidaceæ, Iridaceæ, Bromeliaceæ (in part), Dioscoreaceæ.

Order 1. =Colchicaceæ.= The flower (Fig. 304 A) is ☿, regular, hypogynous, trimerous in all five whorls (6 stamens); anthers usually extrorse. Gynœceum with 3 free styles (A, D); fruit a capsule with septicidal dehiscence (E); embryo very small (F). The underground stem is generally a corm or rhizome, seldom a bulb.

=A.= VERATREÆ.--Veratrum; perennial herbs, stem tall with long internodes and broad, folded leaves; the flowers andromonœcious, with free, widely opening perianth-leaves (Fig. 304 A), and globular anthers; inflorescence a panicle.--Zygadenus, Melanthium, Schœnocaulon, Uvularia, Tricyrtis.

=B.= TOFIELDIEÆ.--Narthecium and Tofieldia have leaves alternate (arranged in two rows), sword-like and borne in rosettes; racemes or spikes. Narthecium forms an exception to the order by having a simple style and fruit with loculicidal dehiscence; Tofieldia by the introrse anthers. In this they are related to the Liliaceæ. Narthecium has poisonous properties, like many other Colchicaceæ.

=C.= COLCHICEÆ.--Colchicum (Autumn Crocus); perennial herbs, with a long, funnel-shaped, gamophyllous perianth, and introrse anthers. The flowers of C. autumnale spring up immediately from the underground stem, which is in reality a corm formed of one internode. ~Colchicum autumnale flowers in autumn without leaves; in spring the radical foliage-leaves appear simultaneously with the fruit. The flower is protogynous, and is pollinated by insects (humble-bees, etc.) which seek the honey secreted by the free part of the stamen a little way down the tube. The length of the tube protects the fruit, and not, as in other cases, the nectary.--Bulbocodium and Merendera have unguiculate perianth-leaves, free, but closing together like a tube.~

175 species; chiefly in North America and South Africa. Tofieldia is an Arctic plant. The order is rich in pungent, poisonous alkaloids (veratrin, colchicin, etc.). OFFICINAL; the seeds of Colchicum autumnale (Europe) and Schœnocaulon officinale (Mexico), and the rhizome of Veratrum album (mountains of Central Europe).

Order 2. =Liliaceæ (Lilies).= Flowers as in the Colchicaceæ but with introrse anthers; ovary free, 3-locular, with single style; capsule 3-locular with loculicidal dehiscence.--The majority are herbs with bulbs; the inflorescence is terminal. In many species reproduction takes place by means of bulbils (small bulbs) formed in the axils of the foliage-leaves (e.g. Lilium bulbiferum, lancifolium, etc., Gagea lancifolia, etc.), or in the bracts of the inflorescence (many species of Allium); in many species several buds are developed as bulbs in the axils of the bulb-scales themselves (accessory buds arising close together), and in some the formation of buds is common on the leaves.

=A.= TULIPEÆ, TULIP GROUP. Bulbs. The aerial, elongated stem bears the foliage-leaves. Flowers few but generally large, with free perianth-leaves. Tulipa; style absent, no honey; flowers generally solitary, erect.--Fritillaria perianth campanulate with a round or oblong nectary at the base of each perianth-leaf.--Lilium; perianth widely open, generally turned back with a covered nectary-groove in the centre of each segment. Anthers versatile.--Lloydia; Erythronium.

=B.= HYACINTHEÆ, HYACINTH GROUP. Bulbs. Leaves radical; aerial stem leafless with raceme or spike. In some the perianth-segments are free, in others united. Honey is produced often in glands or in the septa of the ovary (septal glands).--Ornithogalum has a leafy stem; Scilla; Eucomis has a tuft of floral-leaves above the raceme; Agraphis; Hyacinthus; Puschkinia; Chionodoxa; Muscari; Veltheimia; Urginea.

=C.= ALLIEÆ, ONION GROUP. Generally bulbs. Leaves radical. Stem leafless with a compound umbellate or capitate inflorescence of unipared helicoid cymes, which before flowering are surrounded by two broad involucral leaves.--~Allium. Filaments often petaloid and bidentate; in many species bulbils are found in the inflorescence.--Some species have flat leaves: A. sativum, Garlic; A. porrum, Leek; A. ursinum; others have round, hollow leaves: A. cepa, Onion; A. fistulosum, Winter Onion; A. ascalonicum, Eschalot; A. schænoprasum, Chive.~--Gagea; honey is secreted at the base of the perianth, no special nectary; inflorescence few-flowered.--Agapanthus; Triteleia.

=D.= ANTHERICEÆ. Rhizome; raceme; the leaves not fleshy and thick.--Anthericum; Asphodelus; Bulbine; Chlorophytum; Bowiea has an almost leafless stem with curved, climbing branches.

=E.= ALOINEÆ, ALOES. Stem generally aerial and tree-like, bearing on its summit thick, fleshy leaves, often with a thorny edge (Fig. 306). Raceme branched or unbranched.--Aloë; Gasteria; Yucca (has secondary thickening, p. 274).

=F.= HEMEROCALLIDEÆ. Phormium, (Ph. tenax. New Zealand Flax); Funckia (Hosta); Hemerocallis.

At this point the following are best placed: Aphyllanthes (A. monspeliensis); Xanthorrhæa (Black-boy); Xerotes; Lomandra; Kingia; the very membranous, dry perianth of the last resembles that of the Juncaceæ, and also there are only 1–few ovules in the loculi.

POLLINATION by insects. Honey in some is produced on the perianth (see Tulipeæ), in others by glands on the carpels (in the septa and parietal placentæ, septal glands): Hyacinthus, Allium, Anthericum, Asphodelus, Yucca, Funckia, Hemerocallis, etc. Some Allium-species are protandrous. Fritillaria is visited by bees, Lilium martagon by moths, L. bulbiferum by butterflies, Phormium (New Zealand) by honey-birds.

About 1,580 species; rare in cold climates; their home is in sunny plains with firm, hard soil, and warm or mild climate, particularly in the Old World (S. Africa; As. Steppes; Mediterranean); at the commencement of spring the flowers appear in great profusion, and after the course of a few weeks disappear; during the hot season their life lies dormant in the bulb, hidden underground. The woody species are tropical.--The majority of the introduced Liliaceæ (Fritillaria imperialis, Crown-imperial; Lilium candidum; Tulipa gesneriana; Hyacinth; Muscari-species; Scilla-species; Ornithogalum nutans; Hemerocallis fulva and flava; Asphodelus luteus and albus) come from the Mediterranean and W. Asia; Funckia from China and Japan; several Lilies from Japan and the Himalayas; Agapanthus from the Cape; Allium sativum is a native of the Kerghis-Steppes; A. cepa from Persia (?); A. ascalonicum is not known wild (according to others a native of Asia Minor), perhaps a form of A. cepa; A. schænoprasum from the N. temp. region.

Many bulbs have pungent properties; many Onions are used as culinary plants. The bast fibres of Phormium tenax (New Zealand Flax) are used technically. Dyes are obtained from the Aloe; gum for varnish from the stem of Xanthorrhæa hostile and australe. OFFICINAL; “Aloes,” the dried sap of S. African species of Aloe (A. Africana, A. ferox, etc.); the bulb known as “Squills” from Urginea (Scilla) maritima (Mediterranean).

Order 3. =Convallariaceæ.= This order differs from the Liliaceæ in having the fruit a berry (Fig. 308) and in never being bulbous; the seeds are less numerous.

=A.= CONVALLARIEÆ, LILY OF THE VALLEY GROUP. Rhizome (Fig. 307) and normal foliage-leaves.--Polygonatum: rhizome creeping; aerial shoot leafy, bearing the flowers in racemes in the axils of the foliage-leaves; perianth tubular. P. multiflorum (Solomon’s seal), P. officinale, etc.--Majanthemum: flower 2-merous; perianth almost polyphyllous, spreading. Smilacina. Streptopus (S. amplexifolius; the flowers or inflorescence unite with the entire succeeding internode).--Convallaria (1 species C. majalis, Lily of the valley); flowers in terminal racemes; 2 basal foliage-leaves; perianth globose, bell-shaped. Reineckea carnea (Japan, China) in gardens.--Paris (P. quadrifolia, Herb-Paris); flowers solitary, terminal, 4-merous, polyphyllous; styles 4, free (approaching the Colchicaceæ; it is also poisonous); a whorl of 4 (-more) 3-nerved, reticulate leaves on each shoot.--Ornamental plants: species of Trillium, Aspidistra elatior (Japan).

=B.= ASPARAGEÆ, ASPARAGUS GROUP. Scale-like leaves and green assimilating branches.--Asparagus: horizontal rhizome. The aerial shoots are very richly branched; the numerous needle-like bodies upon the plant are leafless shoots, which are crowded together in double scorpioid cymes in the axils of the scale-leaves; the two first lateral axes, placed outside to the left and right, generally bear flowers. Polygamous.--~Ruscus (Butcher’s broom) is a S. European shrub with leaf-like, ovoid or elliptical shoots (phylloclades) which are borne in the axils of scale-like leaves, and bear flowers on the central line. Diœcious. Stamens 3, united, anthers extrorse. Semele androgyna bears its flowers on the edge of the flat shoot.~

=C.= SMILACEÆ. Smilax (Sarsaparilla) (Fig. 308); climbing shrubs with the leaf-sheath produced into tendrils. The leaves have 3–5 strong nerves proceeding from the base, and are reticulate. Orthotropous or semi-anatropous ovules. Diœcious (Fig. 308 C, E).

=D.= DRACÆNEÆ. Fruit in some a berry, in others a capsule. The stem of DRACÆNA, when old, has the appearance of being dichotomously branched; it has the power of increase in thickness, and may become enormously thick. The Dragon-tree of Teneriffe, measured by Humboldt, attained a circumference of 14 m. and a height of 22 m.; the leaves are large, linear or linear-lanceolate.--Cordyline (East Asia), various species in gardens and greenhouses (Yucca is closely allied). Astelia.

POLLINATION. Paris quadrifolia and Convallaria majalis have no honey, and are chiefly visited by pollen-collecting bees (in the absence of insect visits self-pollination takes place); Polygonatum multiflorum has honey secreted by septal glands and protected by the base of the tubular perianth; it is pollinated by humble-bees, etc. Asparagus officinalis has small, polygamous, greenish, honey-bearing flowers; the ♂-flower is almost twice as large as the ♀; both have rudiments of the opposite sex.

About 555 species; especially from N. America, Europe, and Central Asia.

OFFICINAL: “Dragons’-blood,” a red resinous juice from the stem of Dracæna and the roots of some Central American species of Smilax. The tuberous stems of the Eastern Asiatic Smilax glabra are officinal. The flowers of Convallaria majalis have been lately used as a substitute for Digitalis. Pungent, poisonous properties are possessed by Paris. None of the species are used as food, except the young annual shoots of Asparagus officinalis, a shore-plant which is used as a vegetable.

Order 4. =Pontederiaceæ.= Flowers generally zygomorphic, hypogynous, ☿, with handsome, white or violet, petaloid perianth which forms a tube at its base. The stamens are inserted at different heights in the perianth-tube, and are reduced to three (in Heteranthera seldom to one). In some the ovary is trilocular with ∞ ovules (Eichhornia), in others reduced to one loculus with one ovule (Pontederia). Fruit a capsule or nut. Embryo as long as the abundant, mealy endosperm.--Tropical water-plants (22 species) with peculiar sympodial branching, nearly the same as in Zostera. Spikes without floral-leaves. Many intercellular spaces in the stem and leaf.--In greenhouses: Eichhornia azurea, E. crassipes (both from tropical and sub-tropical S. America); the latter has swollen petioles which serve as floats and enable it to float freely on the water, sending down its roots into the mud. Heteranthera reniformis, H. zosterifolia. Pontederia cordata.

Order 5. =Amaryllidaceæ (Narcissi).= The flower is epigynous, otherwise exactly the same as in the Liliaceæ (6 stamens). The majority, like these, are also perennial herbs with bulbs and scapes. The fruit and the other characters as in the Liliaceæ. The external appearance is, however, very different.

=A.= AMARYLLEÆ have bulbs and the leaves generally arranged in two rows; the flowers are borne singly or in umbel-like inflorescences on lateral scapes, while the main axis of the bulb is unlimited. Beneath the inflorescence is an involucre (Fig. 309).--Galanthus, Snowdrop, has a polyphyllous perianth without corona; the three inner perianth-leaves are emarginate and shorter than the outer; the anthers dehisce apically. ~Leucojum differs in having the perianth-leaves equal in length.--Amaryllis has a funnel-shaped perianth, entirely or nearly polyphyllous, but somewhat zygomorphic. Crinum; Hæmanthus; Clivia.~--Narcissus has a tubular corona, a ligular structure arising from the perianth-tube exterior to the outer stamens. ~In Pancratium (Fig. 309) the corona is united with the filaments which appear to spring from its edge. Eucharis amazonica.~

=B.= HYPOXIDEÆ. The leaves, which are grass-like, dry, folded, and in some hairy, spring from a rhizome, generally with a divergence of 1/3. Flowers small, perianth polyphyllous, persistent, on which account perhaps the Hypoxideæ may be considered as the least altered type. The chief characteristic is that the embryo is separated from the hilum. Hypoxis; Curculigo (C. recurvata, a favourite ornamental plant; S.E. Asia).

=C.= ALSTRŒMERIEÆ. (Alstrœmeria, Bomarea); stems long, leafy, often climbing.

=D.= VELLOSIEÆ (Vellosia, Barbacenia); stem woody, usually dichotomously branched, with terminal, single flowers; it bears numerous aerial roots which pierce the leaves and surround the stem. Stamens often (by splitting) 6–18. High table-lands of S. America and S. Africa.

=E.= AGAVEÆ. Very similar to the Bromeliaceæ both in their distribution (nearly all American) and in external appearance. They appear as gigantic bulbous plants with perennial, aerial, generally short stem, and perennial, large, lanceolate or linear, stiff, thick, and often thorny leaves, which form a large rosette; after the course of several (8–20) years the terminal inflorescence is developed, which is 10–12 m. high, paniculate, and freely branched. Before the inflorescence expands, a large quantity of sugar-containing sap is collected from A. americana by removing the terminal bud; this on distillation yields “pulque,” the national drink of Mexico. After flowering the entire shoot dies, but the subterranean lateral shoots survive and reproduce the plant.--Agave americana, etc.; Fourcroya; Polianthes tuberosa (Tuberose; Central America).

DISTRIBUTION. The 650 species are chiefly natives of S. Africa and S. America. Clivia, Hæmanthus, Amaryllis are from the Cape; Narcissus from S. Europe, whence many species have been introduced; Galanthus and Leucojum are especially from S. and Central Europe, and from the Caucasus.

USES, few, except as ornamental plants: Galanthus nivalis; Leucojum; Narcissus pseudonarcissus, N. poeticus, N. jonquilla, N. tazetta, etc.; Amaryllis, Alstrœmeria, Eucharis, Crinum, Vallota, etc. The vascular bundles of the various species of Agave (Agave rigida, var. sisalana, sisal hemp,) are used for cordage, etc.

Order 6. =Bromeliaceæ.= The flowers are hypogynous, epigynous or semi-epigynous; the perianth is divided into calyx and corolla; stamens 6. The fruit is a capsule or berry with many seeds. Endosperm mealy, embryo small, at the edge of the endosperm, but not enclosed by it.

Perennial herbs with a very characteristic appearance (Fig. 310); the stem is most often short, thick, and crowned by a rosette of many leaves, which are long, often very narrow, leathery, stiff, and with a spiny edge; they are usually channeled, completely closing round each other, with their edges forming a tightly closed hollow, in which generally water is collected (this among other things insulates the inflorescence and thus prevents the access of creeping insects, such as ants). The presence of numerous stellate, water-containing hairs often gives the leaves a grey appearance, and the layers of cells beneath the upper epidermis of the lamina form an “aqueous tissue,” which serves as a protection against the rays of the sun and regulates the evaporation. The stomata are often situated in furrows on the underside of the leaf, and hence cause a striped appearance. They are all American (525 species), especially from S. America, where they live partly as epiphytes on trees, partly in the clefts of rocks, often on the steepest slopes, to which they firmly attach themselves by aerial roots; some are terrestrial. The stem is seldom tree-like or many metres in height (Puya, in Chili; Hechtia, in Mexico). The inflorescence is a terminal spike, raceme, or panicle, often with large and brightly-coloured floral-leaves. The flowers are without scent. The seeds, in the species whose fruit is a capsule, are often provided with wings (hairs, expansions, etc).--Ananassa sativa, Pine-apple (W. Indies, Central America) is cultivated for the sake of its juicy, aromatic fruits, which coalesce with their fleshy bracts and form a large spike-like fruit-cluster (multiple-fruits,[29] Fig. 311) bearing on its apex a leafy shoot, which may be used as a cutting. Seeds very rarely developed.--Tillandsia (T. usneoides is a filamentous, richly branched, rootless epiphyte hanging in masses from trees; Trop. Am.), Aechmea, Billbergia, Pitcairnia, etc.

USES. The leaves of the Pine-apple, in its native country, are used for the manufacture of cloth.

Order 7. =Hæmodoraceæ.= 120 species; in all parts of the world except Europe; perennial, often tomentose and resembling the Bromeliaceæ, Iridaceæ and Amaryllidaceæ. Hæmodorum (Australia).--To this order belong Ophiopogon, Peliosanthes, Sanseviera, and others.

Order 8. The =Iridaceæ= have epigynous, hermaphrodite flowers with petaloid perianth as in the Amaryllidaceæ, but the interior whorl of stamens is entirely suppressed, and the 3 developed outer stamens have extrorse anthers (Fig. 279); there is 1 style with 3 large, generally more or less leaf-like branches bearing the stigmas. Ovary and capsule as in the Amaryllidaceæ and Liliaceæ.--Perennial herbs; bulbs are rarely found, but horizontal rhizomes, corms, etc., take their place. The leaves are (except Crocus) as in the Iris, two-rowed, equitant and sword-like. Flowers or inflorescences terminal.

The Iris (Flag) has a horizontal rhizome. The flowers are borne in the leaf-axils in fan-like inflorescences (rhipidium). The branches of the style are large and petaloid; on their under surface may be seen a small projecting shelf (Fig. 312 a) having on its upper surface the stigmatic hairs. Beneath the branches of the style are 3 well protected stamens, and immediately outside these the external perianth-leaves. ~The honey is secreted in the perianth-tube, and the insects, endeavouring to obtain it through the narrow passages at the base of the stamens, settle upon the outer perianth-leaves, which are bent backwards and often very hairy along their central line. The insects then rub their backs on the anthers just above them, beneath the branches of the style; they readily deposit the pollen on the stigma of another flower as they enter it, but cannot do so in withdrawing, since the stigma is pushed back, and self-fertilisation is thus avoided. The stylar branches lie close to the outer perianth-leaves, which are just beneath them, or separated by a distance of only 6–10 mm.; the first form of flower is adapted for Rhingia rostrata, the latter for bees~.--Crocus has vertical, tuberous, underground stems surrounded by the leaf-sheaths (corms), and terminal flowers; the linear leaves are not equitant, but have two longitudinal furrows on the under side. The perianth is gamophyllous and funnel-shaped. The stylar branches (stigmas) are fleshy, rolled together in the shape of a horn, and split along the edge.--Gladiolus has corms like the Crocus; spikes with slightly zygomorphic, almost bilabiate flowers, most frequently turning to one side. Position of the leaves as in the Iris.--~Diplarrhena has 2 fertile and 1 barren stamen; Hermodactylus has a unilocular ovary with 3 parietal placentæ. Cypella and Tigridia have bulbs.~

770 species; chiefly in the countries round the Mediterranean, and in Africa, especially the Cape (Gladiolus, Ferraria, Moræa, Galaxia, Sparaxis, Antholyza, Tritonia, Ixia, etc.), Australia and Tropical America (Sisyrinchium, Tigridia, Cipura, Cypella, etc). A great number are ornamental plants: the cultivated Crocus-species are from the South of Europe and Asia; Gladiolus communis from S. Europe; the other species principally from S. Africa. The native species of Iris are I. pseudacorus (yellow) and I. fœtidissima.

OFFICINAL: the stigmas of Crocus sativus (Oriental, cultivated in France, Spain, Italy, and Austria), used as a colouring matter, saffron; the rhizomes of the S. European Iris florentina, pallida, and germanica (“Orris-root”).

Order 9. =Dioscoreaceæ.= Perennial herbs with fleshy, often very large tuberous rhizomes (or roots); twining stems; leaves stalked, often arrow- or heart-shaped, lobed, palminerved and finely reticulate as in the Dicotyledons (Fig. 313). The flower is diclinous (most frequently diœcious), regular, epigynous, small, and of a greenish colour, but otherwise typical (Pr3 + 3, and A3 + 3, or G3); in most instances 2 ovules are placed one above the other in each loculus. The inflorescence is a spike or raceme, sometimes richly branched and paniculate.--The order approaches most nearly to the Amaryllidaceæ.

Tamus (Bryony) has a berry, Dioscorea (Yam) a thin-walled, 3-edged or 3-winged capsule (Fig. 313). Both have subterranean or aerial tubers; the Yam very often also developes tubers in the axils of the foliage-leaves; tuberous roots are said to occur in D. batatas. The tubers of many species of Yams (D. batatas from China and Japan, D. alata, South Sea Islands and India, D. bulbifera) are a very important source of food in the Tropics, especially the first-named.--Testudinaria; Rajania.--~The tuberous stem of Tamus communis and Testudinaria elephantipes, and some species of Dioscorea is formed from one single internode (epicotyl), and the aerial shoots are developed from adventitious buds; in T. elephantipes the stem is aerial, and covered with thick scales of cork, regularly arranged, and separated by grooves.~

Tropical order (167 species); 2 species (Tamus communis and Borderea pyrenaica) in Europe.

Family 6. =Scitamineæ.=

The flowers belong to the ordinary monocotyledonous type. They are hermaphrodite, epigynous, and have either a petaloid perianth, or calyx and corolla; they are, however, zygomorphic or unsymmetrical, and of the stamens most frequently only one is completely developed, the others being generally represented by petaloid staminodes. The ovary has 3 loculi, more rarely it is unilocular with the suppression of 2 loculi. Endosperm is absent (except Zingiberaceæ); but, on the other hand, there is a large perisperm. To this family belong large, glabrous, especially perennial herbs with rhizomes; leaves large, distinctly divided into sheath, stalk, and blade, the latter being more or less elliptical or lanceolate, entire, with pinnate venation, and always with a very well-pronounced midrib, gradually tapering towards the apex, and giving off numerous branches, which run outwards, towards the margin, at a larger or smaller angle; these lateral veins are closely packed, and parallel, but with only weak, connecting branches between them; the leaves, therefore, are easily torn pinnately (Figs. 314, 317). The leaf-sheaths close tightly round each other and form a false stem.

This very natural family comprises orders closely connected with each other, but is not itself nearly allied to any other family. First in the series stands:--

Order 1. =Musaceæ.= The petaloid perianth is strongly zygomorphic, the anterior leaf being very large (a kind of “labellum”), the posterior one small; only the posterior stamen is wanting, or is rudimentary, the other five are developed, and have quadrilocular anthers; ovary, 3-locular. Seed with straight embryo in mealy perisperm.

The best-known genus is Musa, the Banana (Fig. 314). From the short rhizome arise enormously large, spirally-placed leaves, whose sheaths envelope one another, and form an apparently aerial stem, several metres in height. The inflorescence is a terminal spike with floral-leaves placed spirally, and sometimes magnificently coloured; in the axils of each of these several flowers are situated in two transverse rows (accessory buds); the lowest flowers in the inflorescence are ♀, the central ones ☿, the upper ones ♂, so that fruits are only found in the lower region of the inflorescence, the remaining portion persisting as a naked axis after the floral-leaves and flowers have fallen off; the inflorescence terminates in an ovoid bud formed by the flowers which have not yet opened (Fig. 314, the left-hand figure). The perianth-leaves are united (except the posterior one). The fruit (known as a “Banana”) is a berry, having the form of a smooth, short, three-cornered Cucumber (as much as 30 cm. in length); inside the tough skin is found a farinaceous, aromatic pulp. No seed is developed in the cultivated species.--~Several Musa-species are cultivated in the Tropics for the sake of the fruit (M. paradisiaca, M. sapientum); for the fibrovascular bundles, M. textilis (Manilla Hemp).--Their home is, no doubt, the Tropics of the Old World; they were introduced into America before the arrival of Europeans. Musa ensete has dry, leathery fruits; an ornamental plant.~

In Musa the barren, posterior stamen belongs to the inner whorl; and also in Strelitzia and Ravenala; the latter may have all 6 stamens developed. In Heliconia, on the contrary, it belongs to the outer whorl; in Heliconia the perianth-leaves are differently arranged, and there is only one ovule in each loculus. The three latter genera have dry fruits and leaves arranged in two rows. In the “Travellers’ Palm” (Ravenala madagascariensis) the foliage-leaves form an enormous fan.--Tropical; about 50 species.

The order may be divided as follows:--1. Museæ: Musa, Ravenala, Strelitzia in the Old World. 2. Heliconiæ: Heliconia in the New World.

Order 2. =Zingiberaceæ.= Perianth most frequently divided into calyx and corolla. Calyx gamosepalous. Only 1 fertile stamen (the posterior, Fig. 315, belonging to the inner whorl) with quadrilocular anther, which encloses the style in a furrow; the 2 stamens in the outer whorl are staminodes, the median one (the anterior) is wanting. The 2 lateral staminodes of the inner whorl form the “labellum” (Fig. 315 lab), which usually is the largest segment of the flower, and is often bilobed. Ovules many. The fruit in some is a leathery, 3-valved capsule, with loculicidal dehiscence; in others it is more or less berry-like and indehiscent, or irregularly dehiscent. Straight embryo.--The aerial stem is seldom developed to any extent, and the inflorescences, which are (compound) spikes or racemes, often with coloured floral-leaves, spring in some (e.g. Zingiber officinale) directly from the rhizome. The leaves are arranged in two rows.--The ovary in a few instances (Globba and others) is unilocular, with 3 parietal placentæ.

They are perennial herbs with fleshy and tuberous rhizomes, which are used as condiments and in medicine on account of their pungent and aromatic properties and also for starch, dyes, etc. OFFICINAL: rhizomes of Zingiber officinale (Ginger, unknown wild, but cultivated generally in the Tropics), of Curcuma longa (Turmeric, a dye, E. India) and C. zedoaria, of C. angustifolia and others (as E. India Arrowroot), of Alpinia officinarum, China (galangal). “Preserved Ginger” from Alpinia galanga. Similar aromatic materials (volatile oils) are present also, for example, in the fruits; Cardamom fruits and seeds (from Elettaria cardamomum, China, seldom from E. major).

315 species; Tropics, preponderating in the Eastern Hemisphere, India, and especially S. Asia, whence all the aromatic species originate; they are now commonly cultivated in the Tropics. Some are ornamental plants in greenhouses, e.g. Hedychium, Costus, etc. Globba (with axillary buds in the inflorescence, as in Ficaria), Renealmia, Kæmpferia.

Order 3. =Cannaceæ.= American herbs without aromatic properties. Flowers asymmetric (Fig. 316). Calyx polysepalous. The stamens are petaloid (Fig. 316 st) and barren with the exception of one (the posterior), which bears on one of its edges a bilocular anther; another, which is especially large and coloured, is termed the labellum. The style is compressed and leaf-like, with a small stigma at the apex. Ovules numerous in the 3 loculi. The capsule is furnished with warts or soft prickles. Embryo straight.

Canna (30 species; Trop. Am.). The inflorescence is a terminal spike with 2-flowered unipared scorpioid cymes in the axils of the floral-leaves. Ornamental plants: Canna indica, etc.

The diagram of the andrœcium of the Cannaceæ and Marantaceæ may be represented in the following manner (calyx, corolla and gynœceum being omitted):--

CANNACEÆ. MARANTACEÆ.

w w w w st st w lab wi c * *

w The lateral staminodes, “wings;” st fertile stamen; * the suppressed stamen; lab labellum; c hood; wi inner-wing.

The labellum of the Cannaceæ corresponds with the hood of the Marantaceæ and not with the labellum of the Zingiberaceæ.

Order 4. =Marantaceæ.= The flower is asymmetrical. Only 1 or 2 of the 3 stamens in the outer whorl are present as staminodes; in the inner whorl 2 are petaloid and of the sixth stamen one-half is developed as a staminode and the other half bears a bilocular anther. One ovule only in each loculus. The style is strongly curved and at first enclosed in one of the staminodes (hood) of the inner whorl; later on it springs elastically forward towards the other staminode (inner-wing) of the same whorl. The stigma is very oblique or 2-lipped. Two of the three loculi of the ovary, in some (Maranta, Thalia) become small and empty. Embryo curved. Leaves in two rows, with sheath, stalk, and blade (Fig. 317); at the base of the last is a characteristic swelling (articulus).--~Phrynium, Calathea, Stromanthe, Ctenanthe, Saranthe, etc. About 150 species; tropical, especially America. The starch of the rhizome of Maranta arundinacea is OFFICINAL, “West Indian Arrowroot.”~

Family 7. =Gynandræ.=

The flowers are hermaphrodite and constructed on the ordinary 3-merous, pentacyclic type with petaloid, epigynous, strongly zygomorphic perianth, and generally one-stamened by the suppression of the other 5 stamens. The family has derived its name from the fact that the stamen is united with the style into a “stylar column” (except Burmanniaceæ). All are herbs; many grow as epiphytes on other plants.

This family and the Scitamineæ occupy correspondingly high positions among the Monocotyledons; these two families may therefore be placed close together, although one cannot be derived from the other. The first of the two orders is very small, but the second is very rich in species. The Apostasieæ are best classed with the Orchidaceæ and have no independent place.

Order 1. =Burmanniaceæ.= This order forms a transitional link between the Gynandræ and the epigynous Liliifloræ (Amaryllidaceæ), in having a 6-leaved perianth, and 6–8 stamens; but some have a labiate perianth (the median perianth-leaf of the outer whorl being very large). The ovary is most frequently unilocular with three parietal placentæ; but in some it is 3-locular with axile placentation. Capsule. Seeds ∞, small, with endosperm. The relationship to the Orchidaceæ is shown especially in the very imperfectly developed embryo and in the ovary. Small, tropical herbs (59 species); some are saprophytes.

Order 2. =Orchidaceæ.= The epigynous, petaloid perianth is strongly zygomorphic in having the posterior leaf of the interior whorl, the lip (labellum), differing from all the other leaves in form, size, and colour (except Apostasieæ); the position of the labellum is very frequently reversed, being turned forwards and downwards by the twisting of the ovary (Fig. 318 A). Only 1 of the stamens--the anterior of the external whorl--is developed and bears an anther (by the twisting of the ovary it is turned posteriorly and upwards); the others are entirely wanting (indicated by * in Fig. 318 A) or present as staminodes (Fig. 318 A, δ δ) (except Apostasieæ, Cypripedileæ); the filaments are united with the style to form a column (Fig. 318 B), the stylar-column[30] (gynostemium), and the anther (a) is thus placed on its apex and exactly behind or over the stigma (s). The anther is 4-locular; the pollen-grains do not separate (except Apostasieæ, Cypripedileæ) but remain united either in tetrads or in masses, which correspond to a pollen-mother-cell (Fig. 320 C, D, E); or the pollen-grains, formed in each of the two anther-halves, remain united and form one or a few wax-like masses (pollen-masses, pollinia). The 3 carpels form a unilocular ovary with 3 parietal, deeply bifid placentæ (except Apostasieæ, Selenipedilum). Only the two lateral carpels are prolonged and developed into the stigma (Fig. 318 B, s), while the one lying in the median line, which is situated just within the anther (Fig. 318 A), becomes either rudimentary or developed into the “rostellum” (“a small beak”), on which the sticky bodies (glandulæ) arise; by aid of these the heavy, connected pollen-masses may be glued to the insects which visit the flower, and pollination is thus secured (in Apostasieæ and Cypripedileæ the 3 carpels each contribute to the formation of the stigma). The fruit is a capsule which most often dehisces by 6 valves, 3 of which are broader and bear the placentæ, and 3 alternating with them are narrower and barren (except Vanilla). The very numerous and exceedingly small seeds have no endosperm, and have a somewhat spherical embryo without any trace of external organs. The testa is membranous and loose.

The Orchids are all perennial herbs with diverse habits and varying morphological structure (see the genera); the leaves are scattered, of the usual Liliaceous form, and the inflorescences in all cases are racemes or spikes (sometimes branched), with subtending bracts, but without bracteoles.

The forms which are the least modified are described first.

=1.= APOSTASIEÆ. The perianth-leaves are almost alike and free. The column is straight, with 3 equally-developed stigmas. Neuwiedia has 3 perfect stamens (1 median of the outer whorl, and 2 lateral of the inner whorl); Apostasia has only 2 perfect (inner lateral) and one barren (the median of the outer whorl), which however may be entirely wanting. The 3 posterior stamens are entirely suppressed. The pollen is powdery. The ovary is 3-locular with axile placenta. 7 species (Tropical East India, Australia).

=2.= CYPRIPEDILEÆ.[31] The flower is strongly zygomorphic with a large boat-shaped labellum. There are two perfect stamens belonging to the inner whorl, and the median anterior (later on the posterior) stamen of the outer whorl is transformed into a large, barren, shield-shaped body (Fig. 319). Selenipedilum has a 3-locular ovary, but Cypripedilum (Ladies’-slipper) has a unilocular ovary with 3 parietal placentæ--the typical structure for the Orchids. The pollen-grains are separate (not in tetrads) and all the 3 lobes of the stigma are constructed to receive them. This group is therefore, next to the Apostasieæ, the least modified among the Orchids; in all the following groups, one of the lobes of the stigma is differently developed from the others, and there is only one stamen.--Terrestial Orchids.--~The pollination of C. calceolus is effected by the forcible entrance of insects into the boat-shaped labellum (Fig. 319 p’) at i, and their escape at ex (in 2) where the anthers are situated; in this way the stigmas will first be touched and then the anthers. The pollen-grains are surrounded by a sticky mass in order that they may adhere to the insects.~

=3.= NEOTTIEÆ. The majority are terrestrial Orchids with creeping, sympodial rhizomes; the blades of the leaves are not detached from the stem at joints, and have convolute vernation. The anthers do not drop off, but persist in the withered condition; their apex is brought in contact with the rostellum (acrotonous Orchids). The pollen-grains are united in tetrads, which, however, often hang loosely together in pollinia, attached to a sticky part of the rostellum (“adhesive disc”), so that they adhere to the insects, and are by them transferred to the stigmas. Spiranthes. Listera; Neottia. ~N. nidus-avis (Bird’s-nest) is brown (it has little chlorophyll) in colour, has no foliage-leaves, and lives mainly as a saprophyte; the rhizome is studded with unbranched, fleshy roots which may form buds at their extremities.~--Vanilla climbs by aerial roots. The fruit is fleshy and hardly opens, or does so irregularly.--Epipactis, Cephalanthera.--Epipogon and Limodorum are saprophytes without chlorophyll.

=4.= OPHRYDEÆ. Anthers 2-locular, not falling off, on a very short column. The anther is united at its base with the rostellum (basitonous Orchids, Fig. 320 A, B), while in all other Orchids it is connected at the apex (acrotonous Orchids). The pollen-grains in each loculus are united into small “masses” (massulæ), each of which corresponds to a pollen-mother-cell in the anther, and which hang together by elastic threads (Fig. 320 C, E). Each pollinium is attached at the base by a stalk (caudicle) to an adhesive disc, formed by the modified stigma (rostellum), and is easily liberated from it (Fig. 320 C, D, F). The pollinium, which is formed in an anther-loculus, together with its caudicle and adhesive disc, is termed “pollinarium” (Fig. 320 C).--All Ophrydeæ are terrestrial with tuberous roots, two of which are present in the flowering period, an older one (from the preceding year) containing the nourishment for the flowering-shoot of the year, and a young one which is intended to contain the reserve material for the following year. Inflorescence terminal.

Orchis. The lip has a spur; each of the club-like pollinia is attached to its own adhesive disc, the discs being enclosed in a common pouch formed by the rostellum (Fig. 320 C, D). ~Tubers ovate, undivided: O. morio, mascula; tubers palmate: O. incarnata, maculata, majalis.~--Ophrys; no spur, the two adhesive discs are each enclosed in a separate pouch (Fig. 320 F).--Anacamptis and Serapias have one adhesive disc.--Habenaria, Gymnadenia, Platanthera, Herminium, Nigritella, Cœloglossum, etc., have naked adhesive discs (no rostellum).

=5.= EPIDENDREÆ. Acrotonous Orchids with deciduous anthers (except Malaxis); 2-8 wax-like pollinia, with or without caudicles; generally no adhesive discs. Malaxis (the flower is twisted through a complete circle, causing the labellum to be turned upwards), Sturmia and Corallorhiza[32] (Coral-root); the latter has a creeping, coral-like rhizome without roots, and is destitute of chlorophyll except in the ovary. The other two somewhat resemble the tropical Orchids in having the lower internodes of the axis of the inflorescence tuberous. Liparis; Calypso. Most of the genera are tropical epiphytes and many have aerial, green tubers formed from one or more stem-internodes; Dendrobium, Eria, Phaius, Bletia, Epidendrum, Cattleya, Lælia, Pleurothallis, Restrepia, Masdevallia, Bulbophyllum, etc.

=6.= VANDEÆ. These resemble the preceding but have only 2 wax-like pollinia in each anther, which are attached by a caudicle to the adhesive disc of the rostellum. Nearly all are tropical epiphytes. Stanhopea, Catasetum, Maxillaria, Oncidium, Vanda, Polystachya, etc.

6,000 (10,000?) species. The majority live in the Tropics and occur, especially, as epiphytes on trees or in the crevices of rocks, to which they are attached by aerial roots. These aerial roots, like those of Araceæ, are covered by several layers of spirally-thickened cells (tracheides) which contain air and form the velamen--an apparatus to absorb moisture from the air. The roots have a white appearance when the cells are filled with air, which changes to a greenish hue when they are filled with water, the chlorophyll then shining through. They generally have horizontal rhizomes; the ascending shoots, which bear the foliage-leaves, may vary, but they very often swell and assume the form of a tuber, which persists for several years fresh and green after the leaves have fallen off (Fig. 321). Vanilla is an exception (see above). Our Orchids are all terrestrial (or marsh-plants); the largest number of species is found in calcareous soils.

POLLINATION takes place principally by means of insects, but self-pollination occurs in some. The lip serves as a landing-stage for the insect visitors, which, on sucking the honey, cause the adhesive discs, with the pollinia attached to them, to adhere to their bodies (generally to the probosces) and so carry them away to other flowers. In some species parts of the flower are sensitive or irritable, which has some connection with the pollination. Without doubt there are a great many biological differences which are closely connected with the infinite multiplicity of forms; Darwin (1862) has already shown an enormous variety, never even dreamt of before, in the European species. The genus Catasetum has ♂-♀-and ☿-plants with flowers of such different appearances that they have been classed in various genera (Myanthus, Monacanthus). Platanthera is pollinated by hawk-moths; Ophrys, by flies; Epipactis latifolia, by wasps; Orchis, by bees, especially humble-bees, etc.

The DISTRIBUTION OF SEEDS is effected by the wind, the seeds being so exceedingly small and light. Many species moreover have peculiar, elater-like, fine, hygroscopic hairs in the ovary, which eject the seeds in a manner similar to the elaters of the Liverworts.

The USES are few, mostly as ornamental plants in conservatories. The tubers of several Orchis-species are OFFICINAL; they contain starch and mucilage and are used us “salep.” The fruits of Vanilla planifolia are used as condiments and differ from other Orchid-fruits in being rather fleshy and in dehiscing irregularly; the seeds are very small, shining and black.

Class II. =Dicotyledones.=

In this class THE EMBRYO has 2 seed-leaves, a rule from which there are few exceptions (e.g. Ficaria, Cyclamen, Pinguicula, certain species of Corydalis, with only 1; and a few, mostly parasitic forms, e.g. Monotropa, Orobanche, Pyrola, entirely without cotyledons). On germination the cotyledons nearly always raise themselves above the ground as green, assimilating leaves and are then termed aerial or epigean, in contradistinction to the underground or hypogean which are always buried. The structure of the seed varies (endospermous or exendospermous); the embryo may be straight or curved. In many instances the primary root grows as a vigorous tap-root, with weaker branches arising acropetally (in annuals, biennials, many perennials, especially woody plants); but in a large number of herbaceous perennials, which have rhizomes, the root behaves very much as in the Monocotyledons. The roots generally increase in thickness by means of a cambium.

THE STEM, when seen in transverse section, has its vascular bundles arranged in a ring; in reality, however, they form a kind of cylindrical network in the stem; the bundles are open, and thickening takes place by means of a cambium; annual rings are formed in the perennial stems. There is a rich and very varied form of branching. The two first leaves of a shoot (fore-leaves) are placed nearly always to the right and to the left; the same arrangement is found in the two first leaves developed on the flower-stalk, and these are, as a rule, the only two; they are found below the calyx and are usually termed the “bracteoles.” It has become customary to indicate the bracteoles by the letters α and β, according to their sequence of growth, and in that sense these letters will be employed in the following diagrams.

THE ARRANGEMENT OF THE LEAVES varies very much; there is also a great variety of shapes in the leaves and their venation, but the linear leaves, with parallel venation, so frequent in the Monocotyledons, are seldom met with, as also the large sheaths (though the sheath is well developed in the Umbelliferous plants); stipules occur much more frequently.

THE FLOWER is most commonly cyclic, but acyclic or hemicyclic forms also occur. The type which may be taken as a basis consists in the majority of instances, as in the Monocotyledons, of 5 whorls, of which the 4 outer ones (calyx, corolla, and the 2 whorls of stamens) are most frequently 4 or 5 in number and placed in regular alternation, whilst the innermost one (the carpels) has generally fewer members, probably on account of space (Figs. 360, 361, 421, 429, 487, etc.). Trimerous (Figs. 384, 387, etc.) flowers, or those in which the members of the flower are in threes or a multiple of three, also occur, as well as dimerous flowers; other numbers are rare. It is of the greatest importance in connection with the relative position of the members of the flower to the axis and bract (orientation), whether the bracteoles are typically present (even though they may not be developed), or are typically absent. If there are 2 bracteoles present, then their position in a pentamerous flower is often as follows: the first sepal turns obliquely forward, the second is posterior and median, the third obliquely forward, the fourth and fifth obliquely backward; quincuncial æstivation is often found in these buds (Figs. 360, 429, 471, 475, 584). The first and third leaves, in the following chapters, are most frequently alluded to as the “anterior,” the fourth and fifth as the “lateral” leaves. The reversed arrangement, with the median sepal in the front, occurs for instance in Papilionaceæ (Fig. 511), Lobeliaceæ (Fig. 594), Rhodoracecæ. If any bracteoles are present below a tetramerous flower, the relation is generally that 2 sepals (the first ones) stand in the median plane, the two next ones transversely (Fig. 393), and the corolla then adopts a diagonal position (Fig. 397); but a diagonal position of the calyx generally shows that the flower is not, strictly speaking, tetramerous, as in Plantago (Fig. 567), Veronica (Fig. 559 C) and others.

If the bracteoles are not typically present, then the position of the sepals is changed accordingly, and the two outer sepals endeavour to assume the position which the bracteoles would otherwise have occupied, e.g. in Primula (Fig. 547). Other positions are also found when the number of bracteoles is more or less than two.

The leaves which follow the sepals occupy definite positions with regard to them, which we may consider later. An arrangement must, however, be mentioned here; when the flower is “diplostemonous” that is, has two whorls of stamens (thus, Sn, Pn, An + n), these may be arranged in two ways. Either the first-formed whorl of stamens, which are termed the “calyx-stamens,” stands directly in front of the sepals (that is “episepalous”), and is the outermost whorl, and in this case a regular alternation takes place between sepals, petals and the two whorls of stamens, which is also continued into the carpels if their number is the same as that of the other whorls: the carpels are then placed opposite the sepals (Fig. 278) and the flower is isomerous and Gn should be added to the formula above. Or, the calyx-stamens form the innermost whorl, and the corolla-stamens, which are subsequently formed (“epipetalous” stamens), stand outside these (Figs. 360, 429); if the number of carpels is the same as that of the preceding whorls, they are often placed right in front of the petals and the corolla-stamens. The first-mentioned arrangement is termed Diplostemonous, and the second Obdiplostemonous. ~Both arrangements may be found in one and the same order, e.g. Caryophyllaceæ. The size and relation of the members of the flowers, and also the contact with other members in the early stages of their development, play an important part in determining the arrangement.~

The great number of structural arrangements found in this enormously large class, may, as is the case in the Monocotyledons, be further varied by suppression and division of certain leaves (especially the stamens). Instances of this will occur in the following (Figs. 559, 568.--426, 441, 445, etc.).

The Dicotyledons were formerly divided into 3 sub-classes: Apetalæ (those without corolla), Sympetalæ or Gamopetalæ (those with the petals united), and Choripetalæ or Polypetalæ (the petals not united). This division has now been abandoned because it has been proved that the Apetalæ were merely reduced or incomplete forms of the Choripetalæ, and they have therefore been distributed among the various families of the latter sub-class.

With regard to the Sympetalæ (or Gamopetalæ) it may be stated that they form to a very great extent a closely connected and natural group, having in common not only the character that the corolla is gamopetalous and the stamens united with it (this being also found in the Choripetalæ), but also a great many others (such as persistent calyx, cyclic flowers with the formula S5, P5, A5 and as a rule G2, the two carpels being united to form the ovary; seeds with a thick integument and a very small nucellus). They are therefore considered as an independent sub-class, and must be placed at the close of the system of classification as the forms which presumably have arisen the latest. In the future systems of classification this arrangement will very probably be changed, and the first families of the Sympetalæ, the Bicornes and others will for instance be to a certain extent united with the families or orders of the Choripetalæ. The Sympetalæ may certainly be considered as the youngest types, the strongly pronounced metamorphosis supporting this theory, as also the formation of the integument of the ovule, the one thick integument being undoubtedly derived from the coalescence of two--a holochlamydeous ovule, etc.

The Apetalæ and Choripetalæ are united into one sub-class. The leaves of the perianth in this case are, as a rule, free from each other, the structure of the flowers presents many differences, and the ovules have as a rule 2 integuments and a large nucellus. Considerable uncertainty still prevails regarding the arrangement and the relationship of the individual families of the Choripetalæ, and some of the following families are hardly quite natural; but the best arrangement arrived at so far has been adopted here.

At the beginning of the book a review of the orders of the Dicotyledons will be found.

Sub-Class 1. =Choripetalæ. Petals free.=

Family 1. =Salicifloræ.=

Trees and shrubs, which, in the structure of the vegetative shoot and the catkin-like inflorescences, resemble the Quercifloræ, but the structure of the flower differs so much from them, that the only order brought under this heading--Salicaceæ--well deserves to be separated and to form a family of its own, the nearest relatives of which are still doubtful. ~As Juglandaceæ and Myricaceæ also deserve to be placed in a special family, the name Amentaceæ (Catkin-bearers), hitherto applied to all of these plants, cannot be retained as the name of a family.~

There is only one order.

Order. =Salicaceæ= (=Willows=). Trees with simple, scattered, stipulate leaves. Diœcious. The flowers are arranged in simple inflorescences (spikes or racemes) which are termed catkins, and which fall off as a whole after flowering (♂) or after the ripening of the fruit (♀) (Fig. 322). The perianth is very imperfect[33] or wanting, particularly in Salix (Fig. 323 o); the ♂-flower with 2–several stamens and without any trace of a carpel (a, b, c): the ♀-flower has a free bicarpellate ovary, unilocular, and formed from 2 lateral carpels with 2 parietal (median) placentæ and generally ∞ ovules; the style divides into two stigmas (d, e, f). The fruit is a two-valved capsule and the very small seeds bear a tuft of hairs at the base. Endosperm absent.--~The catkins are situated on dwarf-branches, which in some species often develop before the leaves and bear at their base only scale-leaves; in others foliage-leaves are borne beneath the catkins. The vegetative bud commences with 2 bud-scales which are united on the anterior side into a scale. The capsule opens by the dorsal suture. The seed-hairs spring from the funicle.~

Salix (Willow) has short-stalked, most frequently lanceolate leaves and erect catkins with undivided bracts (Fig. 322). The flowers are naked; 1 (o in a-f) or 2 yellowish glands situated in the median line. In the ♂-flower generally two stamens, situated laterally like the carpels in the ♀-flower. ~Various forms are seen in Fig. 323.--The terminal bud of the branches often aborts regularly, the uppermost lateral bud taking its place.~

Populus (Aspen, Poplar) has long-stalked, more or less round or cordate leaves with drawn-out apex; catkin pendulous; lobed bracts; perianth cup-like with oblique edge; stamens usually numerous; stigmas often divided.--~P. tremula (Aspen) has received its name from the tremor of the leaves: cf. “to shake like an aspen leaf.”~

POLLINATION. The Poplars are wind-pollinated. The Willows have sticky pollen and are pollinated by insects. The catkins of the Willows, especially the ♂, are more conspicuous, from the numerous, closely-packed, yellow flowers, rich in honey and pollen. The catkins often appear before the foliage and so are much more easily seen, whilst at this time of the year the number of competing honey-flowers is smaller, and the insect visits consequently more numerous. On many catkins of the Willow the flowers open earliest on the side which is turned towards the sun and in descending order, i.e. the upper flowers develop before the lower ones. Hybrids frequently appear.

There are about 180 species existing in the northern, cold and temperate latitudes. Some in the Polar regions are scarcely more than an inch in height, and have a creeping rhizome (Salix herbacea, polaris, reticulata). Fossil forms are found in the Tertiary and perhaps also in the Upper Cretaceous.

USES. Principally for ornamental trees, as they grow very quickly and are easily propagated by cuttings, S. babylonica, Weeping Willow; S. purpurea; Populus alba, Silver Poplar; P. pyramidalis, Pyramid Poplar--a form of P. nigra; P. monilifera, Canadian Poplar. The wood is very poor and little used; the branches of many Willows are cultivated for basket-making, etc. The wood of the Aspen is used for matches. The bark contains tannin and, in many Willows, a very bitter extract, Salicin (S. pentandra, fragilis). Salicylic acid (officinal) is obtained from Salix. Balsam is extracted from the buds of many Poplars, especially when the leaves are shooting.

Family 2. =Casuarinifloræ.=

Trees with verticillate, scale-like leaves forming sheaths at the nodes. Monœcious. Flowers unisexual. ♂-flowers in catkins; ♀ in short spikes. Pollen-tube entering the ovule at the chalaza, and not through the micropyle. Ovary 1-seeded, unilocular. Carpels uniting into a multiple fruit. Only one order.

Order. =Casuarinaceæ.= Trees (30 species), from Australia and certain parts of S.E. Asia, with peculiar, equisetum-like appearance. The leaves are verticillate, scale-like and united into sheaths. The internodes are furrowed. Branching verticillate. The unisexual flowers are situated in catkins or short spikes. The ♂-flower has a central stamen, surrounded by 2 median, scale-like perianth-leaves and 2 lateral bracteoles. The ♀-flower has a 1-chambered ovary (2 ascending, orthotropous ovules), no perianth, but 2 large, lateral bracteoles which finally become woody and form two valves, between which the nut-like fruit is situated. The multiple-fruits therefore resemble small cones.--Casuarina equisetifolia, cultivated, gives “iron-wood.”

[The Casuarinas differ from the ordinary Dicotyledons in many important respects which may be briefly summarised thus:--The bicarpellate ♀-flower has a well-pronounced stylar-cylinder terminated by two stigmas, but the cavity of the ovary closes very soon after its formation, and in it are developed two parietal ovules; these are united by a bridge of cellulose to the stylar-cylinder or summit of the ovary, and hence the ovules are connected with the walls of the ovary by the bridge (above), as well as by the funicle (below). The archespore is developed from the hypodermal cells at the summit of the nucellus, two primordial mother-cells are first formed and from these by tangential divisions a central cylindrical mass of cells (sporogenous-tissue) is produced which is surrounded by tapetal cells. The cells of the sporogenous tissue correspond to the mother-cells of the embryo-sac of other Angiosperms; they divide transversely and from 16–20 macrospores are formed together with inactive cells which are not crushed together as in the case of other Phanerogams. The sexual apparatus is developed from a single cell, but the number of cells composing this apparatus is subject to variation, the oosphere being accompanied by one or two neighbouring cells which resemble canal-cells rather than synergidæ. The sexual apparatus is found in the majority of the macrospores, but in most of these it remains as a number of naked cells; while in the fertile macrospores the cells are invested by walls of cellulose (usually only one fertile macrospore is found in each ovule). Antipodal cells are never developed. The macrospores elongate considerably towards the chalaza, into which some penetrate. The pollen-tube traverses the stylar-cylinder and enters the ovules at the chalaza, its passage through the tissue of the nucellus being assisted by the prolongation of the macrospores. About the centre of the nucellus the pollen-tube is ruptured; the apical portion which alone takes part in the fertilisation being firmly attached to the macrospore. Although the actual impregnation has not been observed, Treub considers that the endosperm begins to be formed before fertilisation.]

Family 3. =Quercifloræ.=

Trees and shrubs with small, unisexual, monœcious flowers, having no perianth or a simple inconspicuous one. The ♂ and ♀ flowers are very different and generally placed in separate inflorescences. The ♂-flowers are most often adnate to the bracts. The stamens are placed opposite the perianth-leaves, when they are present in equal numbers. The ♀-flower is naked, or has a superior perianth. The ovary at the base is 2- or 3-(-6) locular with 1 or 2 pendulous ovules in each loculus, only one of which is developed; the fruit is a one-seeded nut; endosperm absent; embryo straight. The inflorescences, which are either compound and mixed (small dichasia in spikes) or simple, are here also termed catkins; but, strictly speaking, this term is applied to the ♂-inflorescences only. In all Quercifloræ the leaves are scattered (usually in 2 rows) simple, and penninerved, and with deciduous stipules.

It is worthy of remark that in Betulaceæ, Corylaceæ and Quercus the ovules, and to some extent the loculi of the ovary are not developed till after pollination, so that the development of the pollen-tube proceeds very slowly. The smallness of the flowers, the absence of honey, the dryness and lightness of the pollen, the size of the stigma and the abundance of hairs found on many stigmas are all adaptations for wind-pollination. It is also an advantage that the flowers are generally pollinated before the foliage-leaves are developed, thus preventing the pollen being entangled by the leaves.

The two orders Betulaceæ and Corylaceæ mentioned here are by other authors united into one order. [It is doubtful whether these two should be retained in the family Quercifloræ, as recent researches (p. 273) have shown that they differ from the Cupuliferæ in many important points, and agree with the Casuarinas in the fact that the pollen-tube enters the ovule through the chalaza.]

Order 1. =Betulaceæ= (=Birches=). Monœcious, with thick, cylindrical, compound ♂ and ♀ inflorescences (2- or 3-flowered dichasia in a spike with spirally-placed floral-leaves) (Figs. 324, 326, 328). When the perianth in the ♂-flower is completely developed, it is composed of 4 somewhat united leaves, which are placed opposite the 4 stamens (Figs. 325, 326 A). The female flowers are naked; the ovary is bilocular, with two styles and one pendulous ovule in each loculus. The subtending floral-leaves unite with the bracteoles and form a 3–5-lobed cover-scale, which is not attached to the fruit (Figs. 325 D, 326 B). Fruit a nut without cupule (see Corylaceæ and Cupuliferæ). ~In the bud the leaves are flat. The stipules are deciduous. On germination the cotyledons are raised above the ground. Terminal buds are only found on old Alder trees; the Birch has sympodial branches.~

Alnus (Alder) (Figs. 324–326). In the majority of species the ♂-and ♀-catkins are both developed in the year previous to their flowering, and pass the winter naked and bloom before the leaves expand. ♂-flower: 4 stamens. ♀-flower: the 5-lobed cover-scales of the ♀-catkin are woody and remain attached to the axis, so that the entire catkin when ripe resembles a small cone (Fig. 324 b). Each cover-scale supports two winged or wingless nuts. ~In the native species of Alder the buds are stalked (Fig. 324 k). The bud-scales are formed by the stipules of the lowest leaves.~

Betula (Birch). The ♂-catkins, in the native species, appear in autumn, the ♀-catkins in the flowering year on leaf-bearing, short-lived shoots. ♂-flowers: 2 stamens, divided (Fig. 328 A). The 3-lobed cover-scales (Fig. 327 a) of the ♀-catkin are detached from the axis; each cover-scale supports 3 broadly winged nuts (b). ~The stem has cork with annual rings. The young twigs and leaves have aromatic resin glands.~

THE INFLORESCENCES OF THE ALDER.--In the axil of each cover-scale [b in the Figs] is situated, in the ♂-catkins (Figs. 326 A, 325 A-C) a 3-flowered dichasium, the flowers of which have a 4-partite perianth, the posterior perianth-segments being sometimes almost suppressed, and 4 stamens with undivided filaments. In the ♀-catkin (Figs. 325 D, 326 C) a 2-flowered dichasium is found, the middle flower being suppressed (indicated by a star in C). In both instances the inflorescences have two bracteoles (α-β) and the flowers borne in their axils have each one bracteole (β′), the other one (α′) being suppressed and therefore in 326 A and C only represented by a dotted line; these four bracteoles unite with the cover-scale (b) which supports the entire dichasium, to form the 5-lobed “cone-scale” (Fig. 326 B) which in the ♀-catkin eventually becomes woody.

THE INFLORESCENCES OF THE BIRCH.--A 3-flowered dichasium is situated in the axil of the cover-scale in both ♂-and ♀-catkins (Fig. 328 A, B); only the central flower has bracteoles (α-β) (the lateral flowers having no bracteoles), and these bracteoles unite, as in the Alder, with the supporting cover-scale (b), and form a three-lobed cone-scale (Fig. 327 a).

While the ♀-flower exactly resembles that of the Alder, the reduction of the ♂-flower, already described in the Alder, is carried further, so that often only the 2 median perianth-leaves are developed (Fig. 328 A); there are also only 2 stamens, these being deeply cleft, while the other 2 are suppressed.

About 50 species; N. Temp.--Fossil-forms certainly occur in the Oligocene. During the Glacial period the Dwarf-birch (B. nana) extended over Europe; at the present time it is confined to the moors and mountains of N. Europe and N. America and Asia. Wind-pollinated.

USES.--Important forest trees. The bark contains tannic acid. The tar of the Birch is used in the preparation of Russia leather; whilst its spring sap is very saccharine, and is used in some places for making a fermented drink. Its external bark is used for roofing, for baskets, etc.

Order 2. =Corylaceæ= (=Hazel-nuts=). Monœcious. The ♂-catkins are long and cylindrical; the ♂-flowers are placed singly in the axil of the subtending-leaf (cover-scale); they are naked and formed of a number of divided stamens, which are partly united with the cover-scale, 4 in the Hazel, apparently 8 (Figs. 330 A, 329 B, C), more on the Hornbeam. The ♀-flowers have a very small, superior perianth; in the axil of each cover-scale a 2-flowered dichasium (Fig. 329 D) is present, of which the central flower (* in Fig. 330 B) is suppressed. The gynœceum is bicarpellary as in the Birches; the ovary is bilocular, with two long styles (Fig. 329 D-F); the loculi have 1 (-2) ovules (Fig. 330 B). Each single ♀-flower and fruit is surrounded by a leaf-like covering, the cupule (husk), which is formed of three floral-leaves (namely, the bract of a lateral flower, and its own bracteoles; thus in Fig. 330 B, α, α′, β’ form the cupule for the left-hand flower, and β, α_[1}, β_[1}, the cupule for the right-hand).

Corylus (Hazel-nut, Fig. 329). The long, cylindrical ♂-catkins pass the winter naked, 2–3 together, on short branches. The very small ♀-catkins are enclosed in buds, in which they pass the winter; these buds are situated in the axils of the fallen foliage-leaves, and it is only by their larger size that they may be distinguished from the ordinary foliage-buds. In spring the ♀-catkins are easily recognised by their red, projecting stigmas (Fig. 329 A). The cupule--the “husk”--is tubular, fringed, and envelopes the nut. ~The leaves are alternate and unsymmetrical, the external side being larger than the internal; this is connected with the vernation, the blade being conduplicate in the bud; the stipules are deciduous. The bud-scales are formed of stipules, the most internal having a leaf-blade attached to them which is suppressed in the external ones. The cotyledons remain underground on germination.~

Carpinus (C. betulus, Hornbeam). The ♂-and ♀-catkins do not appear till the leaves are shooting. The ♀-catkin in this instance is also long and cylindrical. The cupule in C. betulus is 3-lobed, and to a slight extent only embraces the base of the ribbed nut (Fig. 331); each lobe corresponds to a floral-leaf. ~Whilst the carpels are placed medianly in Corylus, in Carpinus, on the other hand, they are situated transversely, as in the case of the Betulaceæ. The lamina of the leaf is not conduplicate in the bud, but flat, and folded only along the lateral veins, which are also indicated in the form of the fully-developed leaf; otherwise the vegetative characters are essentially the same as in the Hazel. The cotyledons are aerial.--Ostrya resembles the Hornbeam, but the cupule completely envelopes the nut, as a sac open at the apex (Eur., N. Am., Japan).~

N. Am., Asia, and Europe; 25 species.--Fossil forms in the Oligocene. Wind-pollinated. USES. As timber (Carpinus betulus) and firewood. The fruits of C. avellana (ordinary Hazel-nut), C. tubulosa (Lambert’s nut) and C. colurna (Turkish Filbert) are edible.

Order 3. =Cupuliferæ.= Monœcious. The inflorescences make their appearance with the leaves, arising in the axils of the leaves of the same year. A woody cupule furnished externally with scales or spines is common, and surrounds 1-several flowers (the cupule in the Corylaceæ never encloses more than a single flower or fruit). The ♂-flower has a united perianth, which is, however, 4–6 partite, and encloses an indefinite number of undivided stamens. The ♀-flower has a superior, 6-merous perianth (3 + 3, compare Figs. 332 D, 334); the gynœceum is formed of 3 (or in Castanea 4–6) carpels with a corresponding number of stigmas (Figs. 332 D, H; 334, 335); and the ovary has at the base 3 (-6) loculi (Fig. 333), each of which has 2 pendulous anatropous ovules; the fruit is a one-seeded nut (Figs. 332 H, 336).

The cupule of the Cupuliferæ, according to the opinion of Eichler, is formed by united bracteoles, (compare Fig. 333, where the four valves in the cupule of Castanea are considered as bracteoles of the lateral flowers of the dichasium); according to another view (see Prantl, in Engler’s Bot. Jahrb., viii., 1889), it is a ring-like axial outgrowth independent of the bracteoles of the flower, whose scales and spines are floral-leaves. The cupule in the Oak only encloses the base of the fruit, but in the Eating-chestnut and Beech the fruit is completely enclosed, and consequently the cupule must divide into a number of valves (generally 4) to allow the fruit to escape. In the 3-flowered dichasia of Pasania, Sect. Eupasania (Trop. Ind.), each individual flower has its own cupule of the same structure and development as in Quercus; and, moreover, each group of flowers has externally the typical six bracteoles.

Castanea (Eating-chestnut, Fig. 332). The catkins are erect (A), cylindrical, with the ♀ at the base and the ♂ at the top, or some are entirely ♂ and composed of small dichasia. The cupule (C, F) is 4-valved, provided with spines, and entirely envelops the 3 nuts; it is already developed at the time of flowering.--~♂-flowers are most frequently borne in 7-flowered dichasia, and have a well developed perianth, most frequently consisting of 6 leaves in two whorls (Fig. 332 B), and a large number of stamens. ♀-flowers are most frequently borne in 3-flowered dichasia (Figs. 332 C, 333); the letters in Fig. 333 indicate the older theory, according to which the 4 bracteoles (α′-β′) of the two lateral flowers are thick and united into a single 4-valved, woody cupule, which surrounds the 3 nuts, and is furnished externally with spines; the spines are well developed hair-structures.--6 carpels in two whorls.--The leaves in the vertical shoots have a divergence of 2/5, 3/8, 5/13; on the horizontal shoots they are alternate. The cotyledons remain underground on germination.~

Fagus (Beech). The ♂-catkins are pendulous, capitate; the ♂-flowers have an obliquely bell-shaped, fringed perianth, with 6–20 stamens. ♀-catkins erect, 2-flowered, borne singly in the axil of foliage-leaves of the same year; the ♀-flower has a gynœceum formed of 3 carpels, bearing an epigynous, 6-leaved perianth (Fig. 334). In this genus the dichasium has only 2 flowers, the central one being suppressed. The cupule contains, therefore, only 2 triangular nuts (“mast”). ~All the shoots have the leaves arranged in two rows; the rows are on the underside, being only about 90° distant from each other; the buds on the other hand approach each other towards the upper side. The bud-scales are stipules without laminæ; in vernation the laminæ are folded along the lateral ribs, the upper lateral portion being the largest (as in Hornbeam and Chestnut). The cotyledons are folded, and at germination are aerial, large, and reniform. 4 species (Europe, Japan, N. Am.)--Nothofagus (S. Am., New Zealand, S. Austr.)~

Quercus (Oak, Fig. 335). Catkins simple. ♂-catkins long, thin, pendulous, few-flowered. ♀-catkins erect; the cupule is cup-like, entire, and encloses only the base of the solitary nut (“acorn”).--~The ♂-flower has a similar construction to that of the Chestnut. The ♀-catkin has not more than 5 flowers (single-flowered dichasia, in which only the central flower is developed). The scales on the cupules are no doubt leaf-structures in this case also. According to another theory, the scales are hair-structures; they arise on the internal face of the young cupule apparently in descending, but really in ascending order. The rim of the cupule gradually expands. In the ♀-flower (Fig. 335) the loculi of the gynœceum, together with the ovules, are not developed until after pollination.--The leaves in all cases have a divergence of 2/5; the lowermost leaves on the shoots are reduced to stipules which serve as the bud-scales (5 rows). The laminæ are conduplicate, as in Corylus, and the external side is the broadest. The cotyledons are fleshy and remain underground. 200 species.--Pasania (100 species).~

368 species, in temperate climates, especially in Europe and N. America. Authenticated forests have been found in the Oligocene. The Beech has one species, Fagus sylvatica, in Europe; it is a most important forest tree (in Denmark the most important) and reaches its most northern limit near Alvesund in Norway (60° N.L.), its northern boundary line passing from Alvesund in a zig-zag line through Ludwigsort, south of Königsberg, in Prussia, towards the Crimea. According to Steenstrup and Vaupell, the Beech did not make its appearance in Denmark until a comparatively recent time, the Oak then being partially supplanted. Other species of Beech are found in N. America and Japan. Several species of Nothofagus occur in the South West of S. America, and in the colder regions of the southern hemisphere. The Oaks grow especially in temperate regions, e.g. in Western Asia, N. America, and the mountains of Mexico. Evergreen species are found in Tropical Asia, Himalaya, Japan and the Mediterranean region. In this country there is one species of Oak (Q. robur), of which there are three varieties (Q. pedunculata, intermedia, sessiliflora). The Eating-chestnut is found in the South of Europe, but is cultivated in the midland and southern counties of England.--USES. The wood of these trees is very useful as timber. The wood of Q. tinctoria has a yellow colouring matter (Quercitron-wood). The bark of the Oak contains a large quantity of tannic acid, and is used for tanning; for this purpose also the cupules of Q. vallonea, ægilops, græca, and others from the Eastern Mediterranean, are used under the name of “Valloons.” The Cork-oak (Q. suber; S.W. Europe) is the most important tree from which cork is obtained, its bark being very largely developed and stripped for cork. Gall-nuts are found on many species; those of Q. lusitanica, var. infectoria (Eastern Mediterranean) are officinal, and likewise the fruits (acorns) and the bark of Quercus pedunculata and sessiliflora. Oil is obtained from the Beech “mast.” The nuts of the Chestnut tree are edible.

Family 4. =Juglandifloræ.=

This family resembles the Quercifloræ in the catkin-like inflorescences, the imperfect, unisexual flowers, the epigynous perianth and the woody shoots with scattered leaves, etc., though it is in other respects very dissimilar; one point of difference is the presence of aromatic compounds, but a more important divergence is found in the structure of the gynœceum, which is formed of two carpels with one loculus and has one basal, orthotropous and erect ovule, which, as in the Quercifloræ, does not become developed until after pollination; the fruit too is very different, being generally a drupe. Endosperm absent.

Order 1. =Juglandaceæ (Walnuts).= Leaves scattered, imparipinnate, rich in aromatic compounds. Stipules absent. Flowers unisexual. Monœcious. The ♂-catkins are lateral, generally on naked branches of the previous year, cylindrical, pendulous, many-flowered; the two bracteoles and the 2–4-leaved perianth of the ♂-flower unite with the subtending bract; the ♂-flower has indefinite stamens (6–20 in Juglans, Fig. 337 A-D). The ♀-catkins are terminal, generally on branches of the same year, few-flowered (Fig. 337 F); the ♀-flowers have a superior, 4-leaved perianth, a bicarpellate gynœceum, two styles with stigmas on the internal surface. The ovary, bracteoles and bract all unite together (Fig. 337 E). The fruit is generally a green or black drupe,[34] whose flesh (outer soft portion) in Carya and Juglans ruptures more or less irregularly, and frees the stone (“Walnut”).--~The stone in Juglans is divided internally by one true (Fig. 337 H) and by several false, low partition walls into several incomplete compartments, so that the two large cotyledons become lobed and incised to fit like a cast into the irregularities of the inner surface of the stone; the embryo is exendospermous and covered with a thin testa.--THE LEAF SCARS are large and cordate with 3 groups of vascular bundles. The PITH in Juglans and Pterocarya is divided into chambers. The stone ruptures, on germination, along the dorsal suture into 2 valves; the cotyledons remain underground. In Juglans regia a long row of accessory buds is found on the lowest internode (epicotyl) above the axils of the cotyledons. Pollination by the wind. Both protogynous and protandrous examples of Juglans regia occur.--33 species, mostly in temperate North America.--USES. Walnuts are obtained from J. nigra and regia; Hickory from North American species of Carya. The oil-containing seeds of several species are edible. Pterocarya and others are cultivated as ornamental plants.~

Order 2. =Myricaceæ=. To this order belong shrubs or trees which have penninerved, simple, at most lobed or pinnatifid leaves, with or without stipules, and with yellow, aromatic, resin glands (Fig. 338 a). The flowers, situated in catkin-like spikes, are unisexual and naked, and supported by scale-like floral-leaves. ♂-flower: 4–6 (–16) stamens with short filaments; ♀: generally situated singly. The gynœceum has a short style with 2 long stigmas, and unites with the bracteoles, which form wing-like outgrowths on the ripe drupe as in Pterocarya in the Juglandaceæ (Fig. 338). Cotyledons fleshy (Fig. 338 b).--Myrica; Comptonia.

40 species; Temperate.--Myrica gale (Sweet-gale, Bog-myrtle) has been used in the preparation of beer (Sweet-willow beer) on account of its resinous essential oil. M. cerifera (N. America) and species from the Cape, M. quercifolia and others, form wax on the fruit which is used in the preparation of candles.

Family 5. =Urticifloræ.=

The flowers are regular, hypogynous, nearly always unisexual, small and insignificant, with single, green perianth of 4–5 leaves. Stamens 4–5, placed opposite the leaves of the perianth. Ovary formed of 1 or 2 carpels, most frequently unilocular, with one ovule (Fig. 340). The fruit is a nut, more rarely a drupe, with one seed, generally endospermous. ~The Nettles are the sole order in the family which has only one carpel (1 stigma); this turns the posterior side to the front (Fig. 340). The others have two carpels (2 stigmas) but the anterior only is fertile (Fig. 346) except in a few Ulmaceæ and Moraceæ.~

The majority are trees or shrubs with petiolated leaves, stipulate; rough hairs are very frequently developed upon the leaves. The flowers are very often crowded together in the inflorescence, which is rarely catkin-like. Peculiar aggregations of fruits are found in some orders. Latex and tough bast, which is used technically, are also frequently found. Cystoliths are found in the epidermis of many species of Ficus, Urtica, and others. ~Wind- or self-pollination is most common, as in the Quercifloræ and Juglandifloræ.~ In ~the Urticaceæ, Morus and some others, the stamens lie incurved in the bud, and when ripe straighten themselves suddenly and elastically, and thus small clouds of pollen-grains are ejected with considerable violence on to the stigmas, which are often provided with brush-like hairs (Fig. 341). The formation of honey does not take place.~

Order 1. =Ulmaceæ= (=Elms=).--Trees or shrubs without latex. Leaves simple, arranged in two rows (divergence 1/2), oblique (the inner side, nearer the axis, being the larger), strongly penninerved, dentate, hispid; stipules deciduous. In opposition to the other Nettle-like plants the flowers are often ☿ with a united cup- or saucer-like, generally 4–(5)–6-divided perianth, and a corresponding or larger number of opposite erect stamens. The gynœceum has two carpels (2 stigmas), generally one loculus with one pendulous, anatropous or amphitropous ovule,[35] seldom two loculi and 2 ovules. Fruit one-seeded (nut or drupe). Embryo without endosperm.

=A.= ULMEÆ. The fruit is a winged nut (Fig. 339), the embryo straight, without endosperm. Anthers extrorse.--Ulmus (Elm). The flowers are situated in inflorescences which develop from the lower buds of the shoot of the preceding year. ~The lowermost bud-scales are empty, the uppermost support either solitary flowers, or small, dichasial or unipared scorpioid inflorescences. The terminal bud on the vegetative shoot quickly falls off, and the upper lateral bud continues the growth sympodially. Flowering takes place before the leaf-buds open. The flowers are wind-pollinated and have no honey. Fossil species have been found in the Oligocene.~

20 species; North Temp. (2 species in this country). Important as timber. The Cork-elm (U. suberosa) has a rather thick cork, which, however, is of no technical use. The bast is used as Lime-bast.

=B.= CELTIDEÆ. The fruit is a drupe, the embryo curved, with folded or rolled up cotyledons, with or without endosperm. The anthers are introrse. The flowers are borne on a shoot of the same year. Planera (N. America); Zelkova.--About 114 species; especially N. Temp., Trop.

Order 2. =Urticaceæ= (=Nettles=).--The majority of species are herbs with simple, stipulate leaves; they have no latex; stinging hairs abundant. The flowers (Fig. 340) are unisexual, generally 2-merous and arranged in clusters, which are united into catkin-like inflorescences. The perianth is composed very often of 4 (2 + 2) free, or in the ♀-flowers generally united, green leaves; the 4 (2 + 2) stamens are opposite the perianth-leaves, the filaments are bent inwards in the bud and throw themselves elastically towards the outside. The gynœceum has one style and one stigma (capitate or brush-like, Fig. 341); the ovary is unilocular, with one orthotropous, erect ovule (all other orders of this family have inverted or curved ovules). Fruit, a nut or drupe. Endosperm present (in Urtica very little), oily. Embryo straight. ~The STINGING HAIRS are club-shaped, very turgid, and provided with a siliceous, brittle apex, which breaks off in an oblique direction and allows the poisonous cell-sap to be forced out. In many tropical Nettles this is so strong that it may produce partial paralysis. There is no rudiment of an ovary in the ♂-flowers (Fig. 340 A). The PERIANTH in the ♀-flower differs from that of the ♂ in having the two internal leaves generally much larger and enveloping the fruit (Fig. 340 B); it often happens that all the perianth-leaves are united to form a gamophyllous envelope. ☿-flowers may occur among the others.--THE INFLORESCENCES among our native species are dichasia, which become transformed into unilateral scorpioid cymes by the development of the bud of the 2nd bracteole. In Parietaria they are more pressed together, and the floral-leaves at the same time are also raised on their axillary shoots to just beneath the flower. As a rule, not only in this order but also in those related to it, a small vegetative branch is situated in the axil of the foliage-leaf, and this bears an inflorescence on each side at its base.~

Urtica (Nettle) has opposite leaves with distinct stipules and stinging hairs. The perianth-leaves of the ♀-flower are free (Fig. 340).--Parietaria (Pellitory) has scattered leaves without large stipules, and stinging hairs are absent. The ♀-perianth is 4-toothed, flask- or bell-shaped.--~Pilea is a tropical genus with trimerous, zygomorphic ♀-flowers, the posterior perianth-leaf being much larger than the two others, and more or less hood shaped.--The flower of Forskohlea is the most reduced; the ♂-flower has only one stamen, and the ♀-as well as the ♂-flowers have a one-sided, tongue like perianth (?). Pouzolzia.~

WIND-POLLINATED. The pollen is shot out of the anthers, when they spring forward, and is caught by long stigmatic hairs. Parietaria diffusa is protogynous (Fig. 341).

500 species; chiefly in the Tropics, although the few species which occur in Europe are represented by a much larger number of individuals.--USES. The bast of the native species Urtica dioica and urens, of U. cannabina (Siberia), etc.; of Boehmeria nivea “Ramié” and “China-grass” (from Sunda Is., China), and others, is used in the manufacture of muslin.

Order 3. =Moraceæ= (=Mulberries=). Nearly all trees or shrubs, seldom herbs, generally with latex. The leaves are scattered, and not infrequently lobed. The flowers are unisexual (monœcious or diœcious) and arranged in catkin- or capitulum-like, compound inflorescences. Perianth-leaves 2–6, generally 4, with an equal number of stamens opposite to them, as in the Nettles. The ovary is 1–seldom 2-locular, and has 2 stigmas (it is thus formed from 2 carpels) seldom only one style with one stigma. One ovule in each loculus, more or less curved, and pendulous; micropyle directed upwards. Fruit usually a drupe. The embryo is generally curved inside the fleshy endosperm, or it is exendospermous.

=A.= MOREÆ. The filaments are incurved in the bud. Leaves folded in the bud--Morus (Mulberry) (Figs. 342–344). Monœcious. The inflorescences are catkin-like in appearance, but in reality composed of many small dichasia. The flowers are similar to those of the Nettle, but with 2 carpels: in the ♂ with perianth 2 + 2, and stamens 2 + 2 (Fig. 342), in the ♀, perianth 2 + 2, and 2 carpels in regular alternation. The small drupes are enveloped by the perianth, which eventually becomes fleshy, and as all the flowers on the axis very accurately fit together, the collection of fruits is formed, which we call a Mulberry (Fig. 344). The leaves are folded in the buds, and have small stipules. ~The following are allied to Morus:--Maclura, Broussonetia (the Paper-mulberry tree) which has spheroid ♀ inflorescences (made up of dichasia), etc.~

Dorstenia presents an interesting transitional form to the Fig in its flat, open, and, in some instances, lobed inflorescence on which the ♂ and ♀ flowers are sunk in grooves. Indications of a somewhat similar structure are found in certain Nettles, the sympodial axes of the dichasia becoming flatly expanded. The fruits are 1-seeded, but, nevertheless, spring open and eject their seeds.

=B.= ARTOCARPEÆ. Filaments straight in the bud; foliage-leaves with convolute vernation. An interpetiolar leaf-sheath (ocrea) formed in the axil of each leaf by the connate stipules, covers the younger leaves as a hood. It falls off as the leaf expands, and leaves a ring-like scar on the stem.--Ficus (the Fig). The inflorescence (the so-called syconus) has a pear-shaped, fleshy, but hollow axis, on the interior surface of which the flowers are situated (Fig. 345). It is a kind of capitulum, with a hollow receptacle, whose “involucral” leaves close over the entrance to the interior; it is not, however, a simple capitulum, but a coalescence of cymose inflorescences. The edible parts are the fleshy stem-portion and perianth-leaves. The ♂-flower has a 2–6 divided perianth, 1–2 (–6) stamens; the ♀-flower has an oblique ovary. The fruits are drupes, with thin flesh.--~Many species have aerial roots, and some live as epiphytes on trees. POLLINATION, in the edible Fig, is effected by a small Gall-wasp (Cynips psenes L.), which lays its eggs in the Fig, and hence carries the pollen away. Even in very ancient times it was customary to hang infected wild Figs on the branches of cultivated ones, so that the young Gall-wasps, as they emerged, could immediately effect the pollination (caprification). Ficus carica, and other species, have two kinds of ♀-flowers, besides the ♂-flowers. One kind has a short style and no stigmatic hairs, and it is only in the ovaries of these that the wasps lay their eggs (gall-flowers); the other kind has a long style and well-developed stigmatic-hairs, but the wasps cannot reach their ovaries--these are “seed-flowers.” There are, moreover, two kinds of plants of Ficus carica; ♀-plants, which have only seed-flowers, and bear the edible Figs, and ♂-plants (called “Caprificus”), which bear inedible fruits, and have ♂-flowers at the upper part of the Fig, but gall-flowers at the base. [The Caprificus, at Naples, bears three crops of inedible Figs each year, viz. Mamme (April), Profichi (June), Mamnoni (August). The ♂-flowers are produced especially in June, the first Figs being almost entirely ♀, and the last having but few ♂-flowers. Each crop produces a new generation of Fig-wasps. The female wasp enters the Figs on the Caprificus, and lays one egg in each flower, with the result that the flower developes into a kind of gall. The mother-wasp dies within the Fig. The male wasp is wingless; it bites a small passage into the ovaries containing the female wasps, and impregnates them; the female wasps then escape from the Fig, those in the Profichi carrying pollen away with them as they pass out. They then enter another Fig, lay their eggs, and die. The edible Fig-tree similarly has three crops in the year, Fiori di fico, Pedagnuoli, Cimaruoli. The wasps, entering these Figs, are unable to lay their eggs in the ovary, but, nevertheless, they effect cross-pollination on entering the Pedagnuoli, which bear fertile seeds.]~

The flowers of Brosimum are the most reduced. The perianth is wanting, and the ♂-flower has only 1 stamen. Cecropia (Trumpet-tree), in S. Am., has its pith divided into chambers; these are inhabited by ants, which feed upon small food-bodies formed on the swollen base of the petioles. The leaves are petiolated, often shield-like, fringed or lobed, and sometimes with white felted hairs. They serve as food for Bradypus (the Sloth). Sorocea; Castilloa.

About 300 species exclusively in the warmer climates. The white Mulberry (M. alba, from China, India, Mongolia) is cultivated for the sake of its leaves, which are the indispensable food for silkworms. The black Mulberry (M. nigra, W. Asia) is cultivated for its fruits, which are used for the officinal Mulberry juice. The ordinary Fig-tree (Ficus carica) is from the Mediterranean. The fruit of the well-known Oriental Sycamore (F. sycomorus) is edible. The Bread-fruit tree (Artocarpus incisa) and the Jack (A. integrifolia) have their home in the South Sea Islands, and are cultivated in tropical countries. The Bread-fruit is morphologically the same as the Mulberry. It has a very large, spheroid inflorescence, whose floral-leaves and perianth become fleshy and united into one nutritious mass, together with the axis, which is also fleshy. The milky juice of the India-rubber tree (Ficus elastica, East Indies, a common house-plant), and of Castilloa elastica (Am.) is the raw material of India-rubber. The milky juice of Galactodendron utile (Cow-tree, S. Am.) is saccharine and nutritious, but in Antiaris toxicaria (the Upas-tree, of Java) it is a strong poison. The bast of the Paper-Mulberry tree (Br. papyrifera, Eastern Asia); is used in Japan for paper. Shellac is obtained from a small, hemipterous insect (Coccus lacca), which lives upon Ficus laccifera and F. religiosa (the Bo-tree, sacred to Buddha), E. India. The wood of Maclura aurantica (Am.) has a yellow colour, and is known as yellow Brazilian wood.

Order 4. =Cannabaceæ.= The plants which belong to this order are aromatic herbs, either annuals or perennials, without latex. Leaves palminerved, and more or less divided, hispid, and with free, persistent stipules. Flowers always diœcious; ♂-flowers in panicles, formed of dichasia, passing over into uniparous scorpioid cymes. They differ from the Nettles, particularly in the 5-leaved perianth of the ♂-flower, the 5 stamens (Fig. 346–351) with filaments erect in the bud, and in the ♀-flower by the small, entire, cup-like perianth, which surrounds the base of the ovary (Fig. 346, p. 352). The ovary has two styles, or one divided into two, with two stigmas and a pendulous, curved ovule (Fig. 346 B, 352 B); the fruit is a nut; the embryo is curved (Hemp, Fig. 353), or rolled (Hop, Fig. 349), without endosperm.

Only 2 genera with 3 species (Asiatic), of which two are cultivated.--Humulus lupulus (Hop, Figs. 347–349) is a twining, perennial plant, twisting to the right, with opposite, palmilobed, rough leaves, and large, interpetiolar stipules. The ♀-flowers are situated in closely-flowered, cone-like, compound inflorescences, with ultimately large, thin, imbricate floral-leaves (Fig. 348) which bear the yellow, glandular hairs, containing lupulin. ~This inflorescence is made up as follows:--The most external floral-leaves are situated in pairs, and are the persistent stipules of a leaf, the blade of which has become suppressed, or in any case is rudimentary. Such a pair of stipules supports 4 (2–6) flowers in a double uniparous cyme, whose central axis does not develope into a flower. The bracts of these flowers (bracteoles of the partial inflorescence) become, at maturity, very large, spathe-like, and, together with the stipules, produce a cone-like appearance.~

Cannabis sativa (Hemp, Figs. 350–353) is an East Indian herb, with palmilobed leaves, and differs from the Hop in being annual, erect, and in having its leaves opposite at the base and scattered above. The ♀-inflorescence is not cone-like as in the Hop, but the flowers are similar in construction. ~The main difference is to be found in the axillary shoot, which was suppressed in the Hop, and is in the Hemp developed into a leaf-bearing shoot which on each side bears only one ♀-flower, and in the fact that the bracts are not so strongly developed.~

The “Hops” (the female inflorescences) are used in brewing, and medicinally on account of the yellow glands which contain lupulin. The Indian variety of Cannabis sativa contains an abundance of glandular hairs and resin. The withered inflorescences are used in medicine and are officinal. The bast of the stems of the Hemp is also used and the fat oil of the seeds. In Oriental countries the entire plant is used in the preparation of an intoxicating drink (haschisch), the narcotic material being found in the glandular hairs.

Family 6. =Polygonifloræ.=

This family is on one side closely allied to the Urticaceæ by its solitary, basal, vertical, and straight ovule, and by the conical ocrea which envelopes the younger leaves in the bud, similar characters being present in the Urticaceæ. On the other side it is related to the Curvembryæ. The flowers are small, often trimerous, regular and slightly perigynous (~in Chloranthaceæ, if they properly belong to this family, and Houttuynia, more or less epigynous~). Syncarps are present in some Piperaceæ, but the fruit is generally a single fruit, one-seeded berry, nut or drupe. The leaves are generally scattered.

Order 1. =Polygonaceæ.= The majority are herbaceous plants with round, often jointed stems, scattered leaves and ocrea, that is a membranous, tubular, ligular or stipular structure inside the base of the leaf, which clasps the stem and axillary bud; the edges of the lamina are rolled backwards in the bud. The flowers are regular, small, generally ☿, slightly perigynous, with inconspicuous, simple, green or white perianth of 5–6 free segments; stamens 5–9 (Fig. 354) sometimes arranged in two series; gynœceum 2–3 carpels, ovary unilocular with one basal, straight (orthotropous) ovule, 2–3 free styles. The fruit is a 2–3-angular nut; the embryo, with mealy endosperm, is straight or curved (Fig. 355 H), often unsymmetrical.--~The inflorescences are compound, and generally branch from the axils of the bracteoles, so that the last partial-inflorescences become coiled, uniparous scorpioid cymes; in Polygonum the two bracteoles unite into a membranous tube; in Rheum and Rumex there is only one bracteole.~

Rheum (Rhubarb, Fig. 354 A) has a 6-leaved, petaloid perianth (Pn 3 + 3) and 9 stamens (A 3^2 + 3). The 3-winged nut is not enclosed by the perianth.

Rumex (Dock, Fig. 354 B) has 6 stamens (A 3^2 + 0); the perianth is 6-leaved (Pr 3 + 3), green or red, and the triangular nut is enveloped by the 3 interior perianth-leaves, which point upwards and continue to grow after flowering. These perianth-leaves often have warts on their outer surface. ~The following are monœcious: R. acetosa and R. acetosella.~

Polygonum (Knot-grass, Figs. 354 C, D; 355). The petaloid perianth is most frequently 5-merous (2/5 spiral); 5–8 stamens. The nut is triangular (Fig. 354 C, 355), or lenticular (Fig. 354 D). ~There are two whorls of stamens, the external with introrse, and the internal with extrorse anthers. The gynœceum is often bicarpellate (Fig. 354 D).~

The flowers may be considered as constructed upon the monocotyledonous type. Pterostegia has a perfectly monocotyledonous flower with 5 trimerous whorls. Rheum likewise, but here the external staminal whorl is doubled (Fig. 254 A). Oxyria has a dimerous Rheum-flower (4-leaved perianth, 6 stamens, 2 stigmas). Rumex has a Rheum-flower with the suppression of the internal whorl of stamens (Fig. 354 B); Emex is a dimerous Rumex. Polygonum, to which Coccoloba, Muehlenbeckia and others are related, differs from Rheum chiefly in having one of the leaves, which in the latter takes part in the formation of the perianth, developed in this case into a bracteole (so that the perianth is reduced to five members), and several or all the stamens in the inner whorl become suppressed.--The perianth in Coccoloba and Muehlenbeckia is more or less perigynous and becomes fleshy, enclosing the fruit. Muehlenbeckia platyclada has flat branches with rudimentary leaves; sometimes branches with normal, arrow-shaped leaves are found. Atraphaxis.

POLLINATION. Rumex is wind-pollinated, the stigmas are therefore large and brush-like (indicated in Fig. 354 B). Rheum and Polygonum are insect-pollinated and have therefore capitate stigmas, etc.; honey-glands are situated at the base of the stamens (d, in Fig. 354 C, and n in Fig. 356); a few small-flowered Polygonum species are self-pollinated; Buckwheat (P. fagopyrum) is dimorphic and has long-styled and short-styled flowers (Fig. 356). Pol. bistorta is protandrous and homostyled.

About 750 species, most of which are found in the temperate regions of the Northern Hemisphere, some reaching as far as the snow line or into the Arctic regions (Oxyria, Kœnigia). Trees and shrubs are found in the Tropics: Coccoloba, Triplaris. Rheum is Central Asiatic.--The thick rhizomes of R. officinale (Rhubarb) are officinal. The rhizomes of the ordinarily cultivated species, R. undulatum and rhaponticum, are used in veterinary medicine. The following are cultivated as culinary plants for the sake of their leaves:--Rumex acetosa (Sorrel), R. patientia, R. scutatus, and Rheum undulatum (petioles). Several species of Polygonum (P. hydropiper and others) have a sharp, pungent taste. “Buckwheat” is the mealy fruit of Polygonum fagopyrum (Central Asia) and is of value as a farinaceous food. P. cuspidatum (P. sieboldi, Japan) is an ornamental plant.--Calligonum in sandy and stony deserts.

Order 2. =Piperaceæ (Peppers).= Shrubs or herbs, often with nodose, jointed stem; leaves simple, entire, often with curved veins; stipules wanting (Peperomia) or intrapetiolar and cap-like, often enclosing the terminal buds (Piper). The flowers in the group Pipereæ (Piper, Fig. 357, and Peperomia) are borne in spikes with fleshy axes (club-like), seldom in racemes, the outer ones are crowded and are ☿ or unisexual, always small, naked and without bracteoles; ~generally stamens 3 + 3, and gynœceum 3, but the number of the stamens may be reduced by suppression to 2, and the carpels to 1~. The flowers are situated in the axils of the small, generally shield-like floral-leaves. The ovary is always unilocular and has one upright, orthotropous ovule. Fruit a berry or drupe. Both endosperm and perisperm are present, the latter being especially well developed (Fig. 359).

Piper; generally shrubs with scattered leaves, and terminal inflorescences which are crowded to one side by the development of the highest lateral bud, so that they are situated opposite the leaves (Fig. 357). Many species have stems with an abnormal anatomical structure.--Peperomia; chiefly succulent herbs, often epiphytes, with opposite or verticillate leaves having aqueous tissue on the upper side.

The group Saurureæ (considered by some as an order, and perhaps representing a more original type) has 3–4 carpels with many ovules. Lactoris stands the highest with regular 3-merous perianth, 3 + 3 stamens and 3 carpels, which are united at the base. Fruit a capsule with several seeds. (It has one species from the island of Juan Fernandez, and is also placed in an order of its own, Lactoridaceæ, allied to the Magnoliaceæ, through Drimys).--Saururus has naked flowers; most frequently 6 stamens, and 4 carpels, free or united at the base, each with 2-4 orthotropous ovules. Fruit, small berries.--Houttuynia; stamens situated a little upward on the ovaries; placentation parietal; capsule many-seeded.

About 1,000 species; entirely tropical, especially from South America and East India. They are found chiefly among the underwood in damp, shady places; some, which are fleshy (Peperomia), live as epiphytes on trees; a few climb by roots.--USES. Several Piperaceæ are used medicinally and for spices on account of their pungent properties and the essential oils found in nearly all parts of the plant. The following are officinal: “Black-pepper” (the unripe, dried fruits) and “White-pepper” (the seeds of the ripe fruits) of Piper nigrum (climbing shrub, East Indian); “Cubeb” berries of P. cubeba (climbing shrub, Java). “Long-pepper” is the unripe inflorescence of P. longum, East India. The leaves of P. angustifolia (Matico) are officinal. The leaves of the Betelpepper (East India) are used together with the nuts of the Areca-palm to form the well-known East Indian intoxicating compound “Betel.” A good many others are also used.

Order 3. =Chloranthaceæ.= (Chloranthus, Hedyosmum) have opposite leaves, with stipules more or less united at the base, and inferior “drupes.” Ovules pendulous. Only endosperm. About 33 species, Tropical.

Family 7. =Curvembryæ.=

The plants in this family have a curved ovule, and most frequently a kidney-shaped seed (generally provided with fine, cuticular, projecting warts, Fig. 362 B), with a curved, peripheral embryo enclosing the endosperm which is most frequently floury (Figs. 362 C, 365 H; for exceptions, see Fig. 366); the seeds in all cases are borne on a centrally-placed, and in most cases free, placenta (they are “basal” when there is only 1 ovule in the ovary, Fig. 364). The flower is regular, hypogynous or perigynous (Fig. 364) (only rarely epigynous) and usually 5-merous. The flower which is most complete has 5 whorls (S5, P5, A5+5, G2-3–5), as in some genera of the Caryophyllaceæ (Figs. 360, 361); but from this type it becomes reduced, the petals and stamens being suppressed, so that finally 5 perianth-leaves, 5 stamens (opposite the perianth-leaves), and 2 carpels (Fig. 361 F) only are present; for example, in certain genera of the Caryophyllaceæ, in the Chenopodiaceæ, Amarantaceæ, and others. When the number of stamens is increased to more than 5 in the whorl, it is always possible to show that some of the stamens have been divided. The number of the carpels and ovules also becomes reduced; in the highest there is a central placenta, not free in its early stages, with a large number of ovules; in those which are most reduced there is only a single ovule, which is placed centrally at the base of the ovary [Fig. 364]. Somewhat corresponding changes are found in the fruit, which is a many-seeded capsule in those which have many ovules, but a one-seeded nut where there is one ovule. In the most reduced forms the flowers are generally unisexual.--Similar features are also present in the vegetative parts. Almost all the species are herbaceous, the leaves are simple and most frequently without stipules. ~The structure of the stem, especially in Chenopodiaceæ, Amarantaceæ, Nyctaginiaceæ and others, often differs from that of the ordinary Dicotyledon. In the woody portion of the stem and root several rings are sometimes formed which resemble annual rings but which are formed by new cambium-rings arising outside the old ones which then cease to divide.~

Order 1. =Caryophyllaceæ.= Herbaceous plants, with round, nodose stem; leaves opposite, slightly amplexicaul, simple, with sessile, undivided, entire lamina; stipules nearly always absent; the inflorescences are dichasia passing over into unipared scorpioid cymes. The flowers are regular, ☿ or unisexual, hypogynous or perigynous, 5-(or 4-) merous with 2–3–4–5 carpels; calyx persistent; corolla polypetalous. The ovary is unilocular (or originally, and sometimes also in the later stages, plurilocular below, e.g. Viscaria), with free styles and 1–several curved ovules on a central, free placenta. The fruit is a nut or a capsule opening apically with long or short valves (teeth, Fig. 362), equal to or double the carpels. For the seeds refer to the family. ~In Dianthus the embryo is straight.~

The flowers which are most complete have Sn, Pn, An + n (obdiplostemonous), Gn where n = 5 (Figs. 360, 361 A) or 4 (Fig. 361 B); the carpels may be placed opposite to the sepals (Fig. 360) or opposite to the petals (Fig. 361 A, B). Without any change taking place in the position of the other whorls, the carpels are next found reduced to 2–3–4 (see the genera); their number may easily be recognised by that of the styles. This is the construction in the majority of the genera in the two first groups. Stellaria media differs considerably. It may have (a) the flower as described above, with G3; (b), the corolla only absent, or (c) only the petal-stamens (A5 + 0, Fig. 361 C), or (d) all these as well as some of the sepal-stamens. The same applies to Sagina, Alsine, Cerastium, and others, and, finally, a series of genera are formed, with certain conditions of reduction which have become constant, and by a gradual series of steps lead to the most reduced form, which has only 5 sepals and 5 (or even as far as only 1) sepal-stamens (Fig. 361 D, E, F).--The PETALS in the Alsineæ are often deeply bifid. The sepal-stamens are most frequently the longest, and bear nectaries at the base (Fig. 363 st). In the most complete forms the ovary has partition-walls in the lower portion (Fig. 360); these do not, however, reach to the top, and generally soon disappear. The ovules, when numerous, are situated on the placenta in as many double rows as there are carpels. In the number of ovules a reduction from many to 1 takes place (Fig. 361). A comparison proves that the “free, centrally placed” placenta is formed by the ventral portion of the carpels. The single basal ovule in Herniaria (Fig. 364), Scleranthus, and others, is also borne on the carpels.

The vegetative branching is characteristic. One of the leaves in a pair is formed before the other, and has a more vigorous axillary bud; these stronger leaves stand in a ¼-spiral, the fifth above the first one, and the branches are consequently arranged in the same manner. In the inflorescence, however, it is the upper or second bracteole (β) whose axillary bud (w in Fig. 361) is most advanced. The bud of the first bracteole (α) becomes sometimes entirely suppressed, or in some this bracteole itself is suppressed.

The most original type appears to be represented by the Alsineæ. From this form on one side the Sileneæ, adapted in a higher degree for insect-pollination, are developed, and on the other side the Paronychieæ, with various reductions.

=1.= ALSINEÆ, STITCHWORT GROUP. Sepals free, and connected with them stellately expanded, slightly unguiculate (white or inodorous) petals; these, however, often become suppressed (Fig. 363). The fruit is a capsule.

=a.= As many carpels as sepals (4 or 5). Cerastium (Chickweed). The petals are bifid. Capsule cylindrical, frequently curved at the top, and opening by 10 teeth (Fig. 362).--~Malachium differs only in the 5-toothed capsule with bifid teeth.~--Spergula (Spurry). The petals are not bifid, capsule 5-valved; seeds winged. The leaves are linear, and appear as if placed in large numbers in a whorl, a branch being situated in the axil of each with leaves placed very close together at its base; stipules membranous.--~Sagina has Sn, Pn, An + n, or An, Gn, where n = 4 or 5. The corolla is often wanting.~

=b.= 3 (rarely 2) carpels (Fig. 361 C). Stellaria (Stitchwort) has deeply cleft petals. The number of stamens varies (see above).--Arenaria has entire petals. ~(To this group belong Alsine, Moehringia, Halianthus, or Honckenya (Fig. 363), which differ from each other, especially in the form of the seed and number of the capsular valves.) Spergularia has membranous stipules, as in Spergula.--Holosteum.~

=2.= PARONYCHIEÆ (Figs. 361 D, E, F; 364). Small, greenish plants. The leaves, in the majority, are opposite, with membranous stipules. The flowers are most frequently arranged in small dichasia; they are small and insignificant, perigynous (Fig. 364) or hypogynous. The corolla is in most cases wanting, and when present is very small; in general the calyx-stamens are developed, but the corolla-stamens may be represented by small scales (Fig. 364). Ovary most frequently with 1 ovule. Fruit, a nut, rarely a capsule; it is enclosed by the strongly perigynous floral axis (torus).

Scleranthus (Knapwell) is perigynous with bell-shaped torus; no corolla; corolla-stamens are wanting or rudimentary; some calyx-stamens may also be absent.--Corrigiola (Fig. 361 D); Illecebrum; Paronychia (Fig. 361 E); Herniaria (Figs. 361 F, 364).

=3.= SILENEÆ, PINK OR CARNATION GROUP. This has a gamosepalous calyx and unguiculate, white or red, petals, with outgrowths (ligule, corona, paracorolla) at the throat of the corolla. These structures are not found in the other groups, and are merely outgrowths at the junction of the limb and claw. The corolla, stamens and ovary are frequently raised above the calyx, upon a lengthened internode (gynophore). The flower has S5, P5, A5 + 5; fruit a capsule with many seeds.

=a.= 5-(rarely 3–4) carpellate ovary.--Lychnis (Campion, Fig. 360). The corolla is longer than the calyx; corona present. The capsule is 10- or 5-toothed, completely 1-chambered or 5-chambered at the base,--the genus has been divided accordingly into several genera: Melandrium, Lychnis, Viscaria. ~Some species are unisexual by the abortion of stamens or carpels (L. vespertina, diurna).~ Agrostemma (A. githago, Corn-cockle, Fig. 361 A) has a long-toothed calyx, the teeth exceeding the corolla; corona absent; 5-toothed capsule.

=b.= Tricarpellate.--Silene (Catch-fly). Six-toothed capsule; corona present in the majority.--~Cucubalus has berry-like fruits which finally become dry but do not dehisce.~

=c.= Bicarpellate (2 styles, 4-toothed capsule).--Dianthus (Pink); at the base of the calyx 1–several pairs of floral-leaves are situated; corona absent. The straight embryo is a peculiar exception.--Gypsophila has a campanulate, open calyx, 5-nerved, membranous between the nerves; corona absent; the flowers are generally small and numerous, in a large, paniculate dichasia.--Saponaria (Soapwort) has corona.

POLLINATION. Alsineæ has ordinary nectaries at the base of the calyx-stamens (Fig. 336): they are frequently protandrous but may often, in the absence of cross-pollination (in the less conspicuous species) pollinate themselves. Their open flowers are accessible to many kinds of insects (particularly flies and bees). Gynodiœcious flowers are found in several species, and the ☿-flowers are then generally more conspicuous than the ♀-flowers. That the ♀-flowers have descended from ☿-flowers is seen by the large staminodes found in them (Fig. 363). Arenaria peploides is diœcious (Fig. 363). The Sileneæ are as a rule adapted for pollination by insects with long probosces--especially butterflies,--and they are frequently protandrous, so that at first the calyx-stamens open, later on the corolla-stamens, then the stigmas expand. The honey is secreted by a ring-like nectary round the base of the ovary or by nectaries at the base of the stamens. Some only blossom and emit scent at night or in the evening (Lychnis vespertina, Silene nutans, Saponaria officinalis) and, like other night-flowers, are of a white or pale colour.

DISTRIBUTION. 1,100 species, especially in temperate climates, fewer in the colder zone, less still in the Tropics. The Paronychieæ are especially found in dry, sandy fields.

USES. “Soap-root” (with Saponin, forming a lather in water) from Saponaria officinalis was formerly officinal, and Gypsophila struthium. The seeds of Agrostemma githago are said to be poisonous.--The following are ornamental plants: species of Pinks (D. caryophyllus, garden Pink, often with double flowers; D. barbatus, plumarius, etc.). Lychnis, Gypsophila, Silene, Cerastium (C. tomentosum as edging for borders), Saponaria officinalis (often coronate).--Spergula arvensis is sometimes cultivated.

Order 2. =Amarantaceæ.= The flowers are essentially the same as in the Chenopodiaceæ and the extremely reduced Caryophyllaceæ (Fig. 361 F); they are regular, hypogynous, generally ☿, have 5 free (rarely slightly united) perianth-leaves; in front of these 5 stamens, which are often united at their base into a shorter or longer tube and have stipule-like teeth between them (the division Gomphreneæ has 2-locular anthers, each of which opens longitudinally); and a 2–3 carpellate gynœceum with one loculus and most frequently one, more rarely several ovules; the fruit is a nut, more rarely (in Celosia, Amarantus, Gomphrena) a capsule, dehiscing irregularly, or like a pyxidium. The characters which especially separate them from the allied orders are found in the perianth. The perianth-leaves are not green and herbaceous, but membranous, dry, and often coloured; they are frequently produced into a bristle or awn; they have also both subtending floral-leaves and 2 large bracteoles similar to the perianth; all these dry leaves persist without alteration after the withering of the flower.--The flowers are without scent. They are arranged in spike- or capitulum-like inflorescences; sometimes placed singly, sometimes aggregated in the panicle-like inflorescences; in others, on the contrary, in dichasia. The majority are herbs, some are shrubs. The leaves are scattered, or opposite, but always simple and without stipules; some are smooth, others hairy.

450 species; especially in the Tropics, principally S. Am. and E. Ind.: few are found outside these countries.--Only a few are used; some, chiefly E. Indian species, are cultivated as ornamental plants: Amaranthus (Fox-tail); Gomphrena globosa; Celosia cristata (Cock’s-comb) remarkable for its fasciated inflorescence; Alternanthera. Some are employed as culinary plants in the Tropics, and in a few of the E. Indian species the seeds are farinaceous, and used for food.

Order 3. =Chenopodiaceæ.= Generally herbaceous plants like the Caryophyllaceæ, but the leaves are arranged spirally (except Salicornia), and are simple, exstipulate; they are generally fleshy and like the stem “mealy,” that is, covered with small hairs, whose large spherical terminal cell readily falls away; otherwise they are seldom hairy. The inflorescences are generally flower-clusters borne in panicles. Bracteoles generally absent. Flowers generally unisexual: with the single exception of Beta the flowers are hypogynous; they are regular, small and inconspicuous, with single, green, 5-leaved, but more or less united perianth; 5 stamens opposite the perianth, and a 2–5-carpellate, unilocular ovary with 1 basal, curved ovule; but in some genera the number of the perianth-leaves and stamens is reduced to 3–2–1–0. The fruit is generally a nut,--thus this flower and fruit are the same as in the reduced Caryophyllaceæ (Fig. 361 F). The seed is similar to that generally found in the family (for exceptions see the genera).

The floral diagram most frequently present is the same as in Fig. 361 F. There is no indication of corolla or of corolla-stamens, which may be supposed to have belonged to the plant, but which are now entirely and completely suppressed. This order appears to have been an offshoot from the Caryophyllaceæ.--The perianth persists after the withering of the flower, and envelopes the nut; it is very variable, and, together with the position of the seed, the form of the embryo, the sex of the flowers, etc., gives the characters of the genera.

=1.= CHENOPODIEÆ, GOOSEFOOT GROUP (Fig. 365), has ☿ (or polygamous) flowers, with regular 5-parted perianth (C); the embryo is ring-like (H). The leaves have the ordinary flat forms.--Chenopodium (Goosefoot). The flower is hypogynous, and the fruit (which is compressed) perfectly free; Mulberry-like collections of fruits are formed in some species (sub-genus Blitum) by the perianth becoming finally fleshy and coloured.--Beta (Beet, Mangold, Fig. 365) differs from all genera in the perianth, which finally becomes cartilaginous, being epigynous (D). Small, most frequently 2–3-flowered clusters without bracteoles, situated in a long, interrupted axis (A, B); the flowers and fruits in each cluster are more or less united individually, and fall off together--they are commonly known as seeds (E, F). The seed lies horizontally.--Hablitzia (H. tamnoides).

=2.= SALSOLEÆ, SALTWORT GROUP, has cylindrical or semi-cylindrical leaves. Perianth as in the preceding group; the fruit is most frequently compressed. The two first mentioned genera differ from most of the others in the order in having a spirally-coiled, and not a ring-like embryo, so that the endosperm is slight or wanting (Fig. 366). These plants are sometimes placed as a group by themselves, SPIROLOBEÆ--in contradistinction to which the others are termed CYCLOLOBEÆ.--Salsola (Saltwort); leaves subulate, with spiny tips; the flowers have 2 spinous bracteoles: during the ripening of the fruit a tough leathery wing is developed transversely to the back of the perianth.--~Chenopodina deviates from Chenopodium chiefly in the embryo and want of endosperm.--Kochia has a somewhat similar perianth to Salsola, but a ring-like embryo; it differs from the others in being hairy.~

=3.= SALICORNIEÆ, GLASSWORT GROUP. Salicornia (Glasswort) has a very different appearance. The stems are succulent, jointed, and almost leafless; the leaves opposite, very small, sheath-like and connate; there is a depression in the axil of each leaf, in which a small 3-flowered dichasium without bracteoles is sunk; the flowers have a trimerous perianth, 1–2 stamens and 1 carpel. No endosperm. S. herbacea on clayey beaches.

=4.= ATRIPLICEÆ. This group has most frequently unisexual flowers; the ♂-flower has a 4–5 partite perianth, but the ♀-flower differs from it. Atriplex is monœcious or polygamous, the ♀-flower is naked, but has 2 large, herbaceous bracteoles which expand during the ripening of the fruit, and often become warted and fringed, enveloping the compressed nut. ~The section Dichospermum has two kinds of ♀-flowers, one like those just described, the other similar to the Chenopodium-flowers, which have been deprived of their stamens, and the fruits of which are depressed, not pressed together from the sides; some (e.g. A. hortensis) have even three kinds of nuts. All the flowers of Atriplex, which present vertical fruits, are accessory shoots, which stand beneath the ordinary flower-clusters, a rather singular relation.~--Spinacia (Spinach) is diœcious; ♂-flower: perianth, 4 (-5); stamens, 4 (-5); ♀-flower: tubular, 2–4-partite perianth, hardening during the ripening of the fruit, and uniting with the compressed nut; in S. oleracea, it also forms thorns; 4 long stigmas.--Halimus has the 2 long bracteoles almost entirely united and ultimately adhering firmly to the fruit.

=5.= BASELLEÆ. A somewhat exceptional group with more or less perigynous flowers and 2 bracteoles. Basella, Boussingaultia, Ullucus. The perianth is sepaloid; ovary 1-ovuled. In Basella the perianth is fleshy, enveloping the nut, and the cotyledons are so rolled together that a tranverse cut divides them in two places (as in Spirolobeæ). Herbaceous climbing plants.

POLLINATION. Wind-and self-pollination, as far as is known; the insignificant flowers, devoid of honey, appear to exclude insect-pollination.--520 species. Most of them are annual (out of 26 native species only 5 are perennial); inhabiting salt-marshes and salt-steppes, and growing as weeds (most frequently on garden or field soil containing manure) in this country, especially species of Chenopodium and Atriplex. The majority are found outside the Tropics, and play a very important part, for example, in the Asiatic salt-steppes. They grow gregariously in large masses.

USES. Comparatively few. The only important one is Beta vulgaris (from the Mediterranean basin), with its different varieties, viz. Beet-root, Cattle-beet or Red-beet, Sugar-beet, and others. These are biennial, making in the first year a root which acts as a reservoir of reserve material, with a rosette of leaves, and in the second year using this material in the production of a long stem, leaves and flowers. The primary root has been developed by cultivation into a very thick and fleshy tap-root; its mode of increase in thickness deviates from that of other roots, concentric rings of vascular bundles being formed from a cambial ring developed outside the previous ring. In this way several rings of vascular bundles separated by medullary rays, alternating with rings of parenchyma, may be found in the root of a Beet. Besides Beta vulgaris, var. hortensis (Beet-root), the following are also cultivated: var. cicla (Leaf-beet, “Mangold,” or “Roman Spinach ”), Spinacia oleracea and Atriplex hortensis as Spinach; a form of the latter and of Spinach are grown as ornamental plants. The tubers of Ullucus tuberosus are used as potatoes; Chenopodium quinoa, in Chili and Peru, is an important farinaceous plant. Soda is made from some (Salsola kali, Chenopodina maritima and others). Aromatic properties are rare: Chenopodium ambrosioides and botrys.

Order 4. =Batidaceæ.= Batis maritima, a bushy West Indian maritime plant.

Order 5. =Phytolaccaceæ.= The ☿ (sometimes unisexual), regular, sometimes slightly perigynous flowers are inconspicuous and have a single sepaloid or coloured 4–5-leaved perianth (generally united at the base); stamens either in 1 whorl in the spaces between the perianth-leaves or in 1 whorl opposite the perianth-leaves, or in 2, one of which alternates with these; but the number may be increased by the splitting of one or of both the whorls to as many as 10–15–20–25. Carpels sometimes only one, sometimes many (4–10) placed in a whorl, either free or united into a gynœceum with a corresponding number of loculi in the ovary; but in all cases each carpel bears only its own style and 1 ovule. The fruit is a berry (or nut, capsule, or schizocarp).--Mostly herbs or herbaceous shrubs, with scattered, simple leaves without stipules (Petiverieæ; have stipules). Inflorescences, most frequently racemes or spikes, which in some instances are apparently placed opposite to a leaf, being displaced by a more vigorous growth of the axillary bud. Embryo always bent.--Petiveria has a straight embryo with rolled cotyledons.--Phytolacca, Pircunia, Microtea, Seguieria, Rivina (Pr4, A4, G1; berry), and others.

The following plant is, with some doubt, placed near this order: Thelygonum cynocrambe; monœcious. ♂-flowers: perianth, 2-leaved; stamens indefinite. ♀-flowers: perianth-leaves united, 3-toothed; G1, style gynobasic. Fruit a drupe. An annual plant; Mediterranean. Branching anomalous.

About 90 species; in tropical and temperate countries, principally America and Africa.--The red juice in the fruits, especially of Phytol. decandra, is used for colouring wine.

Order 6. =Portulacaceæ= (=Portulacas=). The flowers are regular (except Montia), hypogynous (except Portulaca) and ☿. The diagram which applies to the majority of genera is that in Fig. 367, but with all the 5 stamens completely developed: it may be considered as the Chenopodiaceous diagram with the addition of 2 bracteoles in the median line (m-n, these by some are considered as sepals), and with a petaloid perianth (usually designated “corolla”). The “petals” fall off very quickly, and are sometimes wanting. Most frequently 5 stamens, situated opposite the “petals,” but in other genera the number varies; Montia has only 3 stamens (by suppression of the two anterior and lateral, Fig. 367), others again have more than 5, some a large and indefinite number. This may be explained partly by the appearance of a second whorl of stamens alternating with the first, and partly by the splitting (dédoublement) of the stamens. Gynœceum most frequently tricarpellate, ovary unilocular with 1–several basal ovules (sometimes on a branched placenta, as in certain Caryophyllaceæ). The fruit is a capsule, more rarely a nut.--The majority are annual herbaceous plants with scattered, entire leaves, often fleshy and smooth, with or without rudimentary stipules (dry, membranous, modified into hairs). Inflorescence cymose.

Portulaca (Portulaca): flower, epigynous or semi-epigynous; fruit, a pyxidium. The stamens vary in number, and are most frequently placed in groups (in consequence of splitting) opposite the petals.--Montia: the corolla is slightly gamopetalous, but cleft on the posterior side (Fig. 367), and as a consequence of the larger size of the lateral petals, slightly zygomorphic; 3 stamens.--Calandrinia; Talinum; Anacampseros; Claytonia.

125 species; mostly in warm and temperate countries, especially the arid parts of S. Am. and the Cape. Montia fontana (Blinks) is a native plant. Portulaca oleracea is cultivated as a pot-herb in the south of Europe. A few species of Portulaca and Calandrinia are ornamental plants.

Order 7. =Nyctaginiaceæ.= The characteristic feature of this order is the single, regular, united, and often petaloid perianth, the lower part of which generally persists after flowering and embraces the fruit as a false pericarp. The upper portion is most frequently valvate and folded, or simply valvate in æstivation. The number of stamens varies. The free gynœceum is unicarpellate and has 1 ovule. The fruit is a nut, but becomes a false drupe, since the lower persistent portion of the perianth becomes fleshy (as in Neea, where this fleshy part is almost always crowned by the upper persistent part of the perianth. In the majority of the Mirabileæ the lower part becomes the dry anthocarp, while the upper petaloid part falls away after flowering). Finally, a peculiar involucre is formed around the flowers by free or united floral-leaves.--The majority are herbs, some are trees (Pisonia, etc.); Bougainvillea is a liane. The stems are often nodose and swollen at the nodes; the leaves are simple, penninerved, scattered, or opposite, without stipules. ~In some, the vascular bundles are scattered; stem anomalous.~

Mirabilis; the structure of the stem is abnormal. Dichasial branching with continuation from the second bracteole, thus forming unipared scorpioid cymes. The perianth is petaloid, funnel-shaped, and has a folded and twisted æstivation resembling that of the corolla of the Convolvulaceæ; the upper coloured portion falls off after the flowering. Outside, and alternating with it, is a 5-partite, sepaloid involucre of 5 spirally-placed floral-leaves.--Oxybaphus; the involucre envelops 1–3 dichasial flowers.--Bougainvillea; the involucre is rose-coloured, 3-leaved, and envelops 3 flowers (placed laterally; the terminal flower wanting). The leaves of the involucre in Boerhaavia, Pisonia, Neea, and others are reduced to teeth or scales.

157 species; mostly in tropical countries, and especially S. Am. Species of Mirabilis (Am.) are ornamental plants. Theïn is found in Neea theïfera Oersted (discovered by Lund in Lagoa Santa, Brazil), which may be used as a tea-plant.

Order 8. =Aizoaceæ.= Only 3 whorls are found in the flower, which alternate with one another when their leaves are equal in number. The first is sepaloid, the third one the carpels, and the intervening one is either uncleft, in which case it is developed as stamens, or it is divided into a large number of members which then all become stamens (arranged in groups), or the outermost ones become developed as petals. The fruit is most frequently a capsule with several loculi. Most of the species are herbs with thick, fleshy stems, and exstipulate leaves. The structure of the stem is usually anomalous.

=1.= AIZOIDEÆ have hypogynous or perigynous flowers with (4–) 5 perianth-leaves; stamens single, or (by splitting) in groups of 2–3, alternating with the perianth-leaves. The gynœceum (with 3–5 carpels) has 3–5 loculi in the ovary, and most frequently numerous ovules in each loculus, borne on the central placenta formed by the edges of the carpels. The fruit is a capsule. The inflorescences are dichasia and unipared scorpioid cymes.--Aizoon, Mollugo, Sesuvium, and others are herbs or bushes, most frequently hairy.

=2.= MESEMBRIANTHEMEÆ have semi- or wholly-epigynous flowers.--Tetragonia. The perianth is 4 (more rarely 3–5–6)-merous. Stamens single, or (by splitting) in groups alternating with the perianth-leaves. There is an indefinite number of carpels, and each loculus of the ovary contains only 1 pendulous ovule. Fruit a nut or drupe. The flowers arise singly in the leaf-axils, with an accessory foliage-bud below them; in some instances there is also an accessory flower between this bud and the flower. Southern hemisphere, especially at the Cape; T. expansa, New Zealand Spinach, is a fleshy plant which is cultivated as a pot-herb (Japan, Austr., S. Am.).--Mesembrianthemum: the flowers are 5-merous; the numerous linear petals and the still more numerous stamens all arise by the splitting of 5 or 4 protuberances (primordia) alternating with the sepals. The ovary presents another characteristic peculiarity: the carpels alternating with the 5–4 stamens form an ovary (with several loculi) with the ovules at first borne, as in other cases, on the inner corner of the inwardly-turned carpels; but during the subsequent development the whole ovary is so turned round that the placentæ become parietal and the ovules assume, apparently, a position very rarely met with in the vegetable kingdom: on the dorsal suture of the carpels. Shrubs or under-shrubs, more rarely herbs with fleshy stems and simple, entire, more frequently thick or triangular leaves, containing a quantity of water. The flowers open about noon, and are brightly coloured, generally red or red-violet, but odourless. The capsules dehisce in rainy weather. 300 species, mostly found at the Cape. Some are ornamental plants. M. crystallinum (the Ice-plant) and others are covered with peculiar, bladder-like, sparkling hairs, the cell-sap of which contains salt--these serve as reservoirs of water.

Family 8. =Cactifloræ.=

The position of this family is very doubtful; but it seems in many respects to approach Mesembrianthemum. Some botanists place it near to the Ribesiaceæ; others, again, to the Passifloraceæ. Only 1 order.

Order =Cactaceæ= (=The Cacti=). The flower is epigynous, ☿, regular, and remarkable for its acyclic structure; there are, for instance, a large number of spirally-placed sepals and petals, which gradually pass over into one another, and which in some species, to a certain extent, arise from the walls of the ovary as in Nymphæa (Fig. 383 A, B). The petals are free; rotate, opening widely in Opuntia, Pereskia, and Rhipsalis; erect and united at their base into a shorter or longer tube in Cereus, Epiphyllum, Mammillaria, Echinocactus, Melocactus, and others (Fig. 369). Stamens numerous, attached to the base of the corolla; gynœceum formed of many carpels, with one style, dividing into a number of branches corresponding to the number of carpels; the ovary has one loculus with many parietal placentæ; the ovules are anatropous, on long and curved funicles. Fruit a berry with exendospermous seeds. The fruit-pulp is mainly derived from the funicles.--The external appearance of the Cactaceæ is very peculiar; Pereskia, which has thick and fleshy leaves (Fig. 368), deviates the least; foliage-leaves of the usual form are wanting in the other genera, or are usually very small, and quickly fall off and disappear (Opuntia), or are modified into thorns; the stem, without normal foliage-leaves,--so characteristic a feature in this order,--makes its appearance after the two normally developed cotyledons. The stems are fleshy, perennial, and may finally become woody. In some they are elongated, globose, pointed, and more or less dichotomously branched, e.g. in several of the Rhipsalis species, which live mostly as epiphytes on trees; in others, elongated, branched, globose, or, most frequently, more or less angular (prismatic) or grooved and provided with wings, and either columnar and erect (as much as about 20 metres in height and 1 metre in circumference, as in C. giganteus in New Mexico) or climbing by roots (Cereus and Rhipsalis-species); in others again, compressed, more or less leaf-like, often with a ridge in the centre (winged), branched and jointed: Epiphyllum, Phyllocactus, Opuntia, some species of Rhipsalis; others are thick, short, spherical or ovoid, unbranched or only slightly branched, and either studded with prominent warts (mammillæ) each of which supports a tuft of thorns (Fig. 368 A; Mammillaria and others) or with vertical ridges, separated by furrows (rows of mammillæ which have coalesced) in Melocactus, Echinocactus, Echinopsis (Fig. 369); at the same time the ovary in some is embedded in the stem so that leaves or leaf-scars, with tufts of thorns in their axils, may be observed on the ovary just as on the stem.--The flattened shoots of the Cactaceæ are formed in various ways, either by the compression of cylindrical axes (Opuntia) or, as in Melocactus, etc., from winged stems in which all the wings are suppressed except two.

The thorns are produced directly from the growing points of the axillary buds, and are modified leaves. The axillary bud is united at its base with its subtending leaf, which as a rule is extremely rudimentary; and these together form a kind of leaf-cushion, larger in some genera than in others. This leaf-cushion attains its highest development in Mammillaria, in which it is a large, conical wart (see Fig. 368 A), bearing on its apex the tuft of thorns and rudimentary lamina.--The seedlings have normal cotyledons and a fleshy hypocotyl.

All the species (1,000?) are American (one epiphytic species of Rhipsalis is indigenous in S. Africa, Mauritius and Ceylon), especially from the tropical table-lands (Mexico, etc.). Some species, especially those without thorns, as Rhipsalis, are epiphytes. Opuntia vulgaris, the fruits of which are edible, is naturalized in the Mediterranean. The cochineal insect (Coccus cacti) lives on this and some closely allied species (O. coccinellifera, etc.), particularly in Mexico and the Canary Islands. Several are ornamental plants.

Family 9. =Polycarpicæ.=

The flowers as a rule are ☿, regular and hypogynous; however in some orders they are unisexual, e.g. in the Myristicaceæ, or zygomorphic (in Monkshood and Larkspur in the Ranunculaceæ); in the Lauraceæ, (Fig. 386) for example, perigynous, and in Nymphæa (Fig. 383) even partially epigynous flowers are typical.--The flowers are acyclic in very many of the genera of the two first orders, if not completely so, at any rate in the numerous stamens and carpels, thus denoting an old type. It is a remarkable characteristic that in the majority of the orders the number 3 prevails in the calyx and corolla; the number 5 also occurs, but the number 2 is seldom met with. Most orders have a double perianth; chorisis does not occur, suppression is rare, and the parts of the flower are developed in acropetal succession. The most characteristic feature in the order is the free, one-leaved, as a rule numerous carpels (apocarpous gynœceum). The number of carpels in some of the last mentioned orders dwindles down to 1 (e.g. the Berberideæ and Myristicaceæ). The carpels in Nymphæaceæ become united into one pistil (syncarpous), a condition which we also find distributed among the other orders.

Endosperm occurs in almost all the orders (except e.g. Lauraceæ). The nutritive tissue in Cabombeæ and Nymphæeæ is chiefly perisperm.

Order 1. =Ranunculaceæ.= Nearly all are herbs (except Clematis). The leaves are scattered (except Clematideæ), they have a large sheath with broad base (no stipules), and are most frequently palminerved with palmate lobes. The flowers are hypogynous, with most frequently a well pronounced convex receptacle (Figs. 374 B, 380), ☿, regular (except Delphinium and Aconitum); their structure varies very much; in some the leaves are verticillate, in others arranged spirally; in others, again, both modes of arrangement are found. It is a characteristic feature that the various series of leaves (especially calyx and corolla) are not so distinct or so sharply divided as is usual. The leaves of the perianth are free, imbricate (except Clematideæ); stamens numerous, with most frequently extrorse anthers; gynœceum free, apocarpous (except Nigella and partly Helleborus), with 1 or several ovules (Figs. 373, 378, 379) borne on the ventral suture. The fruit is either a nut or a follicle (Actæa has berries). The seed has a large, oil-containing endosperm and a small embryo (Fig. 374).

The main axis generally terminates in a flower, and the lateral axes branch in a cymose manner (Fig. 371). The flowers show the following differences in construction: VERTICILLATE (EUCYCLIC), i.e. constructed all through of alternating whorls: Aquilegia (Fig. 370), Xanthorhiza, and sometimes Eranthis. SEMIVERTICILLATE (HEMICYCLIC) i.e. with sepals and petals in alternate whorls, and the others arranged spirally: Ranunculus (Fig. 371), Myosurus, Pæonia and several other genera entirely, or in certain species only. SPIRAL-FLOWERED (ACYCLIC) i.e. all the leaves are arranged spirally, so that sepals and petals do not alternate the one with the other, even though they are the same in number: Adonis (Fig. 372), Aconitum, Delphinium-species, Nigella-species, Helleborus. The leaves of the calyx are in this instance arranged on a spiral of 2/5; those of the corolla on 2/5, 3/8, 5/13 or 8/21, and stamens and carpels likewise on higher fractions of the same series.

The genera Caltha, Anemone, Thalictrum and Clematis have a single perianth, which is most frequently petaloid; it is thus apparent that the sepals are petaloid, and the leaves, which in other genera have developed as petals, are in these instances stamens. The calyx is similarly petaloid in the genera Helleborus, Eranthis, Nigella, Delphinium and Aconitum; but the petals are present in these instances in unusual (horn-like) forms, and almost entirely given up to the function of nectaries, a function they already possess in Ranunculus. According to a more recent theory the “honey-leaves” are transformed stamens, which have lost the function of reproduction; the perianth is then single, and most frequently petaloid. [Those leaves in the flowers of many Ranunculaceæ which bear nectaries are termed by Prantl honey-leaves, and comprise those leaf-structures of the flower whose essential function lies in the production of nectar, and which, independent of the differentiation of the perianth into calyx and corolla, are derived from the stamens by the loss of their reproductive functions. Clear transitional forms are found between the two series of the perianth (e.g. between the sepaloid and petaloid perianth-leaves of Anemone japonica, A. decapetala, Trollius-species) while transitional forms are never found between perianth-and honey-leaves (with the exception of Aquilegia vulgaris, var. stellata). In Anemone and Clematis the honey-leaves pass gradually into the stamens, and agree with the stamens in the other Ranunculaceæ in their arrangement, development, and scant system of veins (except Nigella). In Delphinium, sect. Consolida, the two honey-leaves placed in front of the unpaired perianth-leaf are united into one, as shown by the veins (twice three veins arranged symmetrically). The honey-leaves of Aquilegia, Callianthemum, and the majority of the Ranunculus-species serve by reason of their large circumference, as organs of attraction, and on this account are considered as petals by other authors.--The same position in the flower which the honey-leaves assume is found occupied by staminodes, without nectar, in some Coptis-species, in Anemonopsis, Actæa sect. Euactæa, (e.g. A. racemosa), Clematis sect. Atragene; in the last-named they closely surround the stamens, in Actæa they are petaloid.--A perianth, sharply differentiated into calyx and corolla, and destitute of honey-leaves, is found in Anemone, sect. Knowltonia (Cape),

Adonis, Pæonia.--The perianth of the Ranunculaceæ is considered by Prantl to be usually petaloid.--The nectaries arise in the Ranunculaceæ (1) on normal stamens (Clematis sect. Viorna), (2) on the honey-leaves (this is generally the case), and (3) on the carpels (Caltha and the majority of Trollius-species).--As the result of his researches upon the Ranunculaceæ, Prantl does not agree with the view advanced by Drude (Schenk, Hand. d. Bot. iii.) that the petals in general have proceeded from the metamorphosis of the stamens (K)].

The most primitive form of fruit is undoubtedly the pod formed by one carpel, on the edges of which (along the ventral suture) two rows of ovules are situated: Pæonieæ, Helleboreæ, Delphinieæ (Fig. 379). In a great many genera the number of ovules has been limited to one perfect one, which is placed in the central plane under the united leaf-edges, and sometimes also some barren ovules above it (Fig. 373). The fruitlets in this case become achenes, and are present in much larger numbers than when there are follicles.

The following have FOLLICLES: Pæonieæ, Helleboreæ (except Actæa) and Delphinieæ; ACHENES: Ranunculeæ, Anemoneæ and Clematideæ.

=A. Follicles= (Figs. 375, 379), with many ovules, situated in two rows along the ventral suture. ~Actæa has berries, Nigella has capsules of several loculi.~

=1.= PÆONIEÆ, PEONY GROUP. This has regular, acyclic flowers with a normal, most frequently 5-leaved, imbricate calyx; large, coloured petals, and introrse anthers. Slightly perigynous. Surrounding the base of the carpels a ring-like swelling of the receptacle (“disc”) is present, which is largest in P. moutan. The follicles are more or less fleshy or leathery. Mostly herbs, with pinnatisect or decompound leaves and large, solitary flowers; a gradual transition may be traced from the foliage-leaves to the petals. Pæonia; Hydrastis.

=2.= HELLEBOREÆ, HELLEBORE GROUP. This has regular flowers with most frequently a coloured calyx. The petals (honey-leaves) are modified into nectaries; they may be horn-like, provided with a spur, or of a similarly unusual form, or they may be entirely absent. Anthers often extrorse.--Trollius (Globe-flower[36]). The flower is acyclic: many petaloid sepals, succeeding these, most frequently, several linear, dark yellow petals, which bear a naked nectary at the base; finally, many stamens and carpels arranged in a spiral (3/8, 8/21).--Caltha (Marsh-marigold, Figs. 375, 377); 5 (-7) yellow sepals, no petals. The foliage-leaves have a large amplexicaul sheath.--Helleborous (Hellebore) has pedate leaves. The flower is acyclic, with 5 large, regular, persistent, often petaloid sepals (2/5); small, horn-like petals (honey-leaves; most frequently 13, divergence 8/13) and generally few carpels (Fig. 374).--Coptis.--Isopyrum.--Eranthis (Winter Aconite), like Anemone, has a 3-leaved involucre and most frequently trimerous flowers, ~6 large petaloid sepals, 6 petals (tubular honey-leaves), 6 oblique rows of stamens, 3–6 carpels~. Aquilegia (Columbine, Fig. 376); the flower is entirely cyclic and has large spurs on all the 5 petals (funnel-shaped honey-leaves); S5 coloured, P5, A5 × (8–12), G5 in regular alternation (Figs. 376, 370); the innermost stamens are often staminodes (Fig. 370).--Nigella (Love-in-the-mist, Fig. 378) has 5 sepals and 8 small, two-lipped petals cleft at the apex (the nectary is covered by the under-lip; Fig. 378 C, D). The 5 carpels are more or less completely united; and a many-carpellate ovary with free styles is formed in some. Large air-chambers in the external wall of the ovary are formed in N. damascena (Fig. 378).--Actæa (Baneberry) has coloured sepals, either no petals or an indefinite number, and only 1 carpel. The fruit is a berry (or follicle).--~Cimicifuga, Garidella, Xanthorhiza (S5, P5, A5 + 5, G5).~

=3.= DELPHINIEÆ, LARKSPUR GROUP. Zygomorphic flowers with coloured calyx; the 2 posterior petals (honey-leaves) are transformed into nectaries, the others are small or absent altogether.--Aconitum (Monkshood); 5 sepals, of which the posterior one (Fig. 379 A) is helmet-shaped; most frequently 8 petals (as in Fig. 372), of which the two posterior ones (honey-leaves) are developed into long-clawed nectaries (Fig. 379 A, k) enveloped by the helmet-like sepal; the others are small, or are to some extent suppressed. ~Stamens on a spiral of 3/8–5/13; generally 3 carpels.~ Perennial herbs.--Delphinium (Larkspur); very closely allied to Aconitum, but the anterior 4 petals are most frequently wanting, and the 2 posterior ones have each a spur, which is enclosed by the posterior sepal, the latter being also provided with a membranous spur. ~Stamens and carpels arranged on a spiral of 3/8, 5/13, 8/21. In D. ajacis and consolida there is apparently only 1 petal (by the fusion of 4) and 1 carpel.~

=B. Fruit achenes.= Many carpels, each with only 1 ascending (Fig. 373 C), or pendulous (Fig. 373 D), perfect ovule; often also rudimentary ovules above it (Fig. 373 A, B). Fruit achenes.

=4.= RANUNCULEÆ, BUTTERCUP GROUP, has double perianth. Myosurus and Adonis have pendulous ovules as in Anemoneæ (Fig. 373 D); ~Ranunculus, with Batrachium and Ficaria, erect ovules (Fig. 373 C) and downwardly-turned radicle.~--Ranunculus. Most frequently S5, P5, many spirally-placed stamens and carpels (Figs. 371, 380). The petals (honey-leaves) have a nectary at the base, covered by a small scale. ~Batrachium, Water Ranunculus, deviates by the achenes being transversely wrinkled; dimorphic leaves. Ficaria has 3 sepals and 7–8 petals arranged in 2/5–3/8. F. ranunculoides (the only species) has tuberous roots, which spring from the base of the axillary buds, and together with these, serve as organs of reproduction. The embryo has only 1 cotyledon.~--Myosurus (Mouse-tail) has small prolongations from the 5 sepals; 5 narrow petals which bear the nectaries near the apex; sometimes only 5 stamens, and an ultimately very long receptacle, with numerous spirally-arranged achenes (Fig. 381).--Adonis is acyclic (Fig. 372); most frequently 5 sepals with a divergence of 2/5, 8 petals of 3/8, indefinite stamens and carpels of 3/8 or 5/13. The corolla has no nectary.

=5.= ANEMONEÆ, ANEMONE GROUP, has a single perianth. ~(Pendulous ovules (Fig. 373 D), radicle turned upward).~--Anemone has a single, petaloid, most frequently 5–6-leaved perianth, and beneath the flower most frequently an involucre of 3 leaves, placed close together in the form of a whorl. In A. nemorosa, ranunculoides, etc., the involucral leaves resemble foliage-leaves; in A. hepatica they are situated close under the perianth, and resemble sepals, and in the sub-genus Pulsatilla they stand between the foliage-leaves and floral-leaves. The style of Pulsatilla finally grows out in the form of a feather. ~The main axis of A. hepatica has unlimited growth (it is biaxial), and the flowers are borne laterally in the axils of the scale-leaves; in the others (uniaxial) the flower is terminal, and the rhizome becomes a sympodium after the first flowering.~--Thalictrum (Meadow Rue) has no involucre; 4–5-leaved, greenish perianth. The receptacle is flat. ~The stamens are brightly-coloured and have long filaments; 1–5 accessory flowers may occur in the leaf-axils of the panicle-like inflorescence.~

=6.= CLEMATIDEÆ, CLEMATIS GROUP. This differs from all the others in the valvate æstivation of the calyx and its opposite leaves. There are 4 (-several) petaloid sepals; petals are absent, or linear (Atragene). Ovule 1, pendulous. Achenes, often with prolonged, feathery style. The majority of the genera are shrubs, and climb by their sensitive, twining leaf-stalks.--Clematis; Atragene.

POLLINATION. The flowers are conspicuous either by coloured petals (honey-leaves) (Ranunculus, Pæonia) or coloured sepals (Helleborus, Anemone, Caltha, etc.), or by both (Aquilegia, Delphinium), or by the coloured stamens (Thalictrum). Some have no honey (Clematis, Anemone, Thalictrum), and are generally visited by insects for the sake of their pollen. Others have nectaries on the corolla (Ranunculus, Trollius, Helleborus, Nigella, Aconitum, etc.), more rarely on the stamens (Pulsatilla, Clematis-species), or the carpels (Caltha), or the calyx (certain species of Pæonia). The honey is readily accessible in the flat, open flowers, and these flowers also may easily pollinate themselves. There is marked protandry where the honey lies deeply hidden, as in Aquilegia, Delphinium, and Aconitum. Helleborus and some Ranunculus-species are protogynous.

About 680 species; especially in northern temperate climates, and extending to the Polar and Alpine regions. Only the Clematideæ are tropical.

The order has an abundance of acrid, vesicant properties (R. acer, sceleratus, etc.), and poisonous alkaloids (Helleborus niger is poisonous). OFFICINAL: Aconitum napellus (aconitine; leaves and tuberous roots); the rhizome of Hydrastis canadensis from N. Am. (the alkaloid hydrastine). The order, however, is best known for its ornamental plants; almost all the genera have species which are cultivated for their beauty. Sweet-scented flowers are absent.

Order 2. =Nymphæaceæ (Water Lilies).= WATER PLANTS; generally with large, floating leaves, and large solitary flowers; sepals 3–5, petals 3–∞, stamens 6–∞, carpels 3–∞. The flower is hypogynous, but in the Nymphæeæ different degrees of epigyny are found, and from this fact, as well as from the carpels being united into one pistil, the family forms a lateral offshoot from the Ranunculaceæ, with much greater modification. The seed often has an aril, and, in the majority, a farinaceous nutritive tissue, partly endosperm, partly perisperm (Fig. 383 C). The embryo has 2 thick cotyledons and a small hypocotyl; the plumule is well developed, with 2–4 leaves.

1. CABOMBEÆ. 3–4 species (Tropical S. Am.), resembling the Water Ranunculus, with two kinds of leaves, the submerged being dissected and the aerial peltate. The flowers are eucyclic, trimerous, with 2–3 free, epigynous carpels. The ovules are situated on the central line of the carpel--an almost unique circumstance. Endosperm and perisperm. Cabomba; Brasenia.

2. NELUMBONEÆ. The leaves are peltate, raised on long stalks high above the water. Large, hypogynous flowers (Fig. 382); sepals 4–5; petals numerous; stamens numerous; carpels several, distinct. The receptacle is very remarkable, being raised above the stamens, and developed into an inverted conical body on the apex of which the nut-like fruits are embedded in pits. Endosperm is wanting, but the embryo is large and has well developed cotyledons.--~Nelumbo, 2 species. N. lutea (N. Am.); N. speciosa (E. Ind.) was sacred amongst the ancient Hindoos and Egyptians, (the Lotus flower); its seeds are used as food.~

3. NYMPHÆEÆ, WATER LILY GROUP. The carpels are united into one, many-locular ovary, whose numerous ovules are situated on the surface of the partition walls (as in the Poppies); the stigma is sessile and radiating, the number of rays corresponding to the number of carpels (Fig. 383). The fruit is a spongy berry with many seeds, which have a large perisperm in addition to the endosperm (Fig. 383 C).

Sepals, petals, and stamens often pass gradually over the one into the other, the petals becoming narrower by degrees, and bearing anthers on each side of the apex, which gradually become larger anthers in proportion to the filament, until the perfect stamen is developed. The long-stalked leaves are floating, and most frequently cordate, elliptical, leathery, with a shiny surface, sometimes (as in Victoria regia and Euryale ferox) with strongly projecting thorny ribs on the lower surface. In the intercellular passages of the leaves are some peculiar, stellate cells.

Nuphar has 5 sepals, and an hypogynous flower. ~The petals, which are small, have a nectary on the back; the coloured inner side of the sepals functions as petals; the ovate gynœceum is quite free.--N. luteum is a native plant (Yellow Water-Lily), with, most frequently, 13 petals and 10–16 loculi in the ovary. The rhizome is horizontal, as much as 5–6 cm. in thickness, and bears on its under surface a number of roots, which on dying-off leave deep scars; the leaves are borne in spiral lines, and the flowers are solitary in certain leaf-axils. The construction of the rhizome is very peculiar; the vascular bundles are scattered and closed as in a monocotyledonous stem.~

Nymphæa has 4 sepals, and the flower is more or less epigynous. Petals and stamens are inserted at different heights on the ovary to just beneath the stigma (Fig. 383). Nymphæa alba (White Water-Lily). Victoria regia from the Amazon, and Euryale ferox from Asia, have entirely epigynous flowers. ~The shield-like leaves of Victoria are as much as 2 metres in diameter, and the edge is bent up to a height of 5–14 cm.; the flowers are 20–40 cm. in diameter, and change in twenty-four hours from white to rose-red. A development of heat, as much as 14°C. above the temperature of the air, together with a strong formation of carbonic acid, has been observed during flowering.~

POLLINATION. Nymphæa alba and other species of the sub-genus Symphytopleura are self-pollinated; the sub-genus Leptopleura is insect-pollinated. Nuphar and Victoria can effect self-fertilisation; Euryale is self-fertilised, often in entirely closed and submerged flowers.--The dissemination of the seeds in Nuphar luteum is effected by the fruit, which rests on the water, becoming detached from its stalk, and dehiscing from the base upwards so that the seeds are set free; while in Nymphæa alba the spirally-twisted stalk draws the fruit under water, and it dehisces by its upper part being thrown off as a hood, and the seeds which are enclosed in air-tight sacs rise to the surface of the water. In this condition they are able to float and can only sink to the bottom when the air has disappeared.

53 species; in fresh water in all parts of the world, but especially in the Tropics.--The rhizomes and seeds of some may be used as food; Euryale ferox is even cultivated. Nymphæa cœrulea and Lotus were sacred among the Egyptians.

Order 3. =Ceratophyllaceæ.= About 3 species. Aquatic plants, submerged, rootless; leaves cartilaginous, verticillate, dissected into repeatedly dichotomous branches which are finely toothed; only one of the leaves in a whorl supports a vegetative branch. The flowers are monœcious, axillary. Inside the 6–12 perianth-leaves are situated in the ♂-flower 10–20 stamens with thick connective, and in the ♀-flower a gynœceum formed by one carpel, with one orthotropous and pendulous ovule, which has only one integument. Fruit a nut, which, in some species, bears on each side a pointed horn, and at the apex a similar one, formed by the persistent style.--The embryo has an unusually well developed plumule with several whorls of leaves. The plant is rootless throughout its whole life.--Ceratophyllum (Horn-wort).

Order 4. =Annonaceæ.= Sepals 3; petals 3+3 (most frequently valvate); succeeding these (as in the Ranunculaceæ) are numerous acyclic stamens and an apocarpous gynœceum; the flowers are hypogynous, regular and ☿, generally very large (2–3 cm. in diameter), and the leaves of the perianth are more or less fleshy or leathery. The majority have syncarps with berry-like fruitlets, but in Annona and some others the carpels fuse together into a large, head-like fruit--a kind of composite berry. The seeds have ruminate endosperm as in Myristica.--Trees or shrubs with alternate, simple, entire, penninerved leaves without stipules. 450 (700?) species; especially tropical. The best known are Anona cherimolia, squamosa and reticulata (all from America) cultivated on account of their large, delicious fruits. Some have acrid and aromatic properties (Xylopia, Cananga--the flowers of the latter yield Ylang-ylang); Artabotrys odoratissimus; Asimina (N. Am.).

Order 5. =Magnoliaceæ.= Trees or shrubs with scattered, often leathery, entire leaves, generally with stipules, which (as in Ficus) are rolled together and form a hood round the younger internodes above them, and are cast off by the unfolding of the next leaf, leaving a ring-like scar. The endosperm is not ruminate. Corolla imbricate. Fruit a syncarp.

=A.= MAGNOLIEÆ. The flowers are borne singly, and before opening are enveloped in an ochrea-like spathe which corresponds to the stipules of the foliage-leaves. The perianth generally consists of 3 trimerous whorls, the external one of which is sometimes sepaloid (Liriodendron, and the majority of _Magnolia_species), sometimes coloured like the others; the perianth is sometimes many-seriate. Numerous spirally-placed stamens and carpels. The latter are situated on the elongated, cylindrical receptacle, and are individually more or less united, except in Liriodendron, where they are free. This last genus has winged achenes; the fruitlets in Magnolia open along the dorsal and ventral sutures, and the seeds then hang out, suspended by elastic threads formed from the vascular bundles of the funicle and raphe; they are red and drupaceous, the external layer of the shell being fleshy--a very rare occurrence.

=B.= ILLICIEÆ has no stipules. The carpels are situated in a whorl on a short receptacle. Follicles, one-seeded. The leaves are dotted by glands containing essential oil. Illicium; Drimys.

70 species; in tropical or temperate climates; none in Europe or Africa. They are chiefly used as ornamental plants, e.g. the Tulip-tree (Liriodendron tulipifera, N. Am.), Magnolia grandiflora (N. Am.), M. yulan and fuscata (China), and others. The remains of Liriodendron occur as fossils in the Cretaceous and Tertiary periods.--The fruits of Illicium anisatum (Star-aniseed from Eastern Asia) are OFFICINAL. The bark of Drimys winteri (S. Am.) is also strongly aromatic.

Order 6. =Calycanthaceæ.= These are very closely related to the Magnoliaceæ, but differ in having perigynous flowers with many perianth-leaves, stamens and (about 20) carpels in a continuous spiral, seeds almost devoid of endosperm with rolled up, leaf-like cotyledons, and leaves opposite on a square stem.--There are some species in N. America (Calycanthus florida, occidentalis, etc.) and 1 in Japan (Chimonanthus præcox), all strongly aromatic.

Order 7. =Monimiaceæ.= Aromatic shrubs with opposite leaves. Perigynous flowers. The anthers dehisce by valves like those of the Lauraceæ, and the Monimiaceæ may thus be considered as an apocarpous form of this order. They are also closely related to Calycanthaceæ. 150 species, tropical.--Hedycarya, Mollinedia, Monimia.

Order 8. =Berberidaceæ (Barberries).=--The regular, ☿, hypogynous flowers are dimerous or trimerous and have regularly alternating whorls of free sepals, petals, and stamens and 1 unilocular carpel; the corolla and stamens have each 2 whorls, the calyx at least 2. The anthers open, as in Lauraceæ, by (2) valves, but are always introrse (Fig. 384). The pistil has a large, disc-like, almost sessile stigma (Fig. 385), and in the ovary several erect ovules are placed close to the base of the ventral suture. The fruit is most frequently a berry. Seeds endospermous.--Shrubs or herbs with scattered, most frequently compound leaves (without stipules), and racemose inflorescences.--~They show a relationship to the Lauraceæ in the number of the parts of the flower and the dehiscence of the anthers.~

Berberis is a shrub; it has sepals 3 + 3, petals 3 + 3, stamens 3 + 3 (Fig. 384). The petals (honey-leaves) bear internally at the base 2 darkish-yellow nectaries. The filaments are sensitive at the base, and suddenly bend inwards if touched at that spot (Fig. 385). ~The racemes often have a terminal, 5-merous flower; they are borne on dwarf-branches. The leaves on the long-branches develope into thorns, but the buds in their axils, in the same year as themselves, develope as the short-branches with simple foliage-leaves, articulated at the base, from which fact some authorities have considered that the leaf is compound with a single, terminal leaflet.~--Mahonia has imparipinnate leaves. The flower has 3 whorls of sepals. Otherwise as in Berberis.--~Epimedium; herbs with spurred petals; the flowers dimerous; 4–5 whorls of sepals, 2 of petals and stamens. Fruit a capsule. Leontice, fruit dry. The anthers of Podophyllum dehisce longitudinally.--Nandina. Aceranthus.~

100 species; North temp., especially Asia: fossils in Tertiary. Berberis vulgaris is a native of Europe. This and other species, together with Mahonia aquifolium (N. Am.), Epimedium alpinum, etc., are cultivated as ornamental plants. Several have a yellow colouring matter in the root and stem. OFFICINAL: the rhizome of Podophyllum peltatum (from N. Am.) yields podophyllin.

Order 9. =Menispermaceæ.= This order has derived its name from the more or less crescent-like fruits and seeds. Diœcious. The flowers are 2–3-merous, most frequently as in Berberis (S3 + 3, P3 + 3, A3 + 3), with the difference that there are 3 free carpels, each with 1 ovule; in some genera, however, the number is different. Stamens often united into a bundle (as in Myristica); anthers dehiscing longitudinally; fruit a drupe.--The plants (with herbaceous or woody stems) belonging to this order are nearly all twining or climbing plants, and have scattered, palmate or peltate, sometimes lobed leaves without stipules. Structure of stem anomalous. Cocculus, Menispermum, Cissampelos, Anamirta.

150 species; Tropical; very rich in bitter and poisonous properties. OFFICINAL: Calumba-root from Jateorhiza columba (E. Africa). The following are cultivated as ornamental plants:--Menispermum canadense (N. Am.) and M. dahuricum (Asia). The fruits of Anamirta cocculus (E. Ind.) are very poisonous (“Grains-of-Paradise”; the poisonous matter is picrotoxine).

Order 10. =Lardizabalaceæ.= This order, by the free, apocarpous carpels, belongs to a more primitive type, and by the united stamens to a more developed one. Akebia; Holbœllia; principally climbing or twining shrubs. About 7 species in S.E. Asia and S. Am.

Order 11. =Lauraceæ= (=True Laurels=). Trees or shrubs; the leaves, always without stipules, are simple, most frequently scattered, lanceolate or elliptical, entire, penninerved, finely reticulate (except Cinnamomum with 3–5-veined leaf), leathery and evergreen (except, e.g. Cinnamomum); they are frequently studded with clear glands containing volatile oil. The flowers are borne in panicles and are small and of a greenish or whitish colour. They are regular, perigynous, with most frequently a bowl or cup-shaped receptacle (Fig. 386), usually ☿, and trimerous (rarely dimerous) through all (most frequently 6–7) whorls; viz. most frequently, perianth 2 whorls, stamens 3–4 and carpels 1 (P3 + 3, A3 + 3 + 3 + 3, G3) in regular alternation (Fig. 387). Each of the 2 or 4 loculi of the anthers open by an upwardly directed valve (Fig. 386); of the stamens, the 2 outermost whorls are generally introrse, the others extrorse, or 1–3 whorls are developed as staminodes (Fig. 387 g). The gynœceum has 1 loculus with 1 style and 1 pendulous ovule (Fig. 386), and may be considered as formed of 3 carpels. The fruit is a berry (Fig. 388) or drupe, which often is surrounded at its base by the persistent receptacle (as an acorn by its cupule), which becomes fleshy and sometimes coloured during the ripening of the fruit. The embryo has 2 thick cotyledons, but no endosperm (Fig. 388).

The Lauraceæ present affinities with the Polygonaceæ, in which there is found perigyny, as well as a similar number of parts in the flower and a similar gynœceum, but with erect and orthotropous ovule. From their general characters they should be classed among the Polycarpicæ, but stand, however, isolated by the syncarpous gynœceum, if it is in reality formed by 3 carpels and not by 1 only. Hernandia, which has epigynous monœcious flowers, deviates most.--Cassytha is a Cuscuta-like, herbaceous, slightly green parasite with twining, almost leafless stems. The flower however agrees with the diagram in Fig. 387. Some Lauraceæ have curved veins or palminerved and lobed leaves (often together with entire ones) e.g. Sassafras.

There are 1000 species; especially in the forests of tropical S. America and Asia, of which they form the principal part. Only Laurus nobilis is found in Europe, and there is little doubt that its proper home is in Western Asia. They are rare in Africa.--On account of the volatile oil found in all parts of the plant, they are used as spices, e.g. the false Cinnamon-tree (Dicypellium caryophyllatum, in the Brazils). The OFFICINAL ones are--the Cinnamon-tree (Cinnamomum zeylanicum from Ceylon, E. India, Eastern Asia), which is also cultivated; the Camphor-tree (Cinnamomum camphora, Eastern Asia). The Laurel-tree (Laurus nobilis, Mediterranean), the berries and leaves of which give laurel oil, is medicinal.--Scented wood for furniture, etc., is obtained from Sassafras officinalis (from N. Am.). The wood from its roots is officinal. Pichurim “beans” are the large cotyledons of Nectandra pichury, whilst the famous “Greenheart” wood of Demarara is the wood of Nectandra rodiæi. The pulp and seeds contain a fatty oil. The pear-like fruit of Persea gratissima (Mexico, also cultivated) is very delicious. Lindera benzoin is a garden shrub; Laurus nobilis likewise.

Order 12. =Myristicaceæ= (=Nutmegs=). In this order there is only 1 genus, Myristica. Trees or shrubs. The leaves agree closely with those of the Lauraceæ, with which this order has many points in common. The majority of the species are aromatic, having in their vegetative parts pellucid glands with volatile oils. The flowers are regular, diœcious, trimerous, and have a single gamophyllous (cupular or campanulate) 3-toothed, fleshy perianth. In the ♂-flowers the anthers vary in number (3–15), and they are extrorse and borne on a centrally-placed column; in the ♀-flower the gynœceum is unilocular, unicarpellary, with 1 ovule. The FRUIT (Fig. 389) has the form of a pear; it is a fleshy, yellow capsule, which opens along the ventral and dorsal sutures, exposing the large seed. This seed has a large, red, irregularly branched aril--the so-called “mace”; the “nutmeg,” on the other hand, is the seed itself with the inner thin portion of the testa, which has pushed its way irregularly into the endosperm, and causes the marbled appearance of the cut seed (Fig. 390); the external, dark brown, hard, and brittle part of the seed-shell is however removed. Mace and nutmeg contain volatile and fatty oils in abundance.--80 species. Tropical. The majority are used on account of their aromatic seeds and aril, the most important being M. fragrans (moschata), from the Moluccas. This is cultivated in special plantations, not only in its native home, but in other tropical countries also. Nutmegs were known as commodities in Europe in very ancient times (e.g. by the Romans), but it was not until the year 1500 that the tree itself was known. The seed is OFFICINAL.

Family 10. =Rhœadinæ.=

The plants belonging to this family are almost exclusively herbaceous, with scattered, exstipulate leaves. The flowers are eucyclic di- or tetramerous, with the calyx and corolla deciduous, hypogynous, ☿, regular, the gynœceum with 2–several carpels (generally 2, transversely placed) (Figs. 391, 392, 393, 397). The ovary is unilocular with parietal placentæ, but in Cruciferæ and a few others it becomes bilocular by the development of a false, membranous wall between the placentæ. The stigmas in the majority of cases are commissural, i.e. they stand above the placentæ, and not above the dorsal line of the carpels. The fruit is nearly always a capsule, which opens by the middle portions of the carpels detaching themselves as valves, bearing no seed, whilst the placentæ persist as the seed-bearing frame. Endosperm is found in Papaveraceæ and Fumariaceæ, but is absent in Cruciferæ and Capparidaceæ.--~This family through the Papaveraceæ is related to the Polycarpicæ (the Nymphæaceæ), through the Capparidaceæ to the Resedaceæ in the next family.~

Exceptions to the above are: Eschscholtzia, Subularia (Fig. 403) and a few Capparidaceæ, in which perigynous flowers are found. A few Papaveraceæ and Fumariaceæ have trimerous flowers. In Fumaria and certain Cruciferæ, the fruit is a nut. The Fumariaceæ have zygomorphic flowers. Trees and shrubs are almost entirely confined to the Capparidaceæ, in which order stipules also are found.

Order 1. =Papaveraceæ= (=Poppies=). Herbaceous plants with stiff hairs and latex; flowers regular (Fig. 391) with generally 2 (-3) sepals (which fall off as the flower opens), 2 + 2 petals (imbricate and crumpled in the bud) without spur, numerous stamens in several alternating whorls (generally a multiple of 2); carpels 2–several, united into a unilocular gynœceum. Trimerous flowers also occur. Capsule with very numerous seeds on the parietal placentæ; embryo small, with large, oleaginous endosperm (Fig. 392).--The leaves have no stipules and are generally pinnately lobed.

Papaver (Poppy) has large, solitary, terminal flowers; petals firmly and irregularly folded in æstivation; gynœceum formed by many (4–15) carpels; stigmas velvety, sessile and stellate (the rays stand above the placentæ) (Fig. 391 B). The edges of the carpels project deeply into the ovary, but do not meet in the centre, so that it remains unilocular. The capsule opens by pores placed close beneath the stigma, and formed of small valves alternating with the placentæ and the rays of the stigma (Fig. 391). P. dubium, P. argemone, P. rhœas.--Chelidonium (Greater Celandine) has yellow latex, flowers in umbellate cymes (the terminal, central flower opening first) and only 2 carpels; the fruit resembles the siliqua of the Cruciferæ in having two barren valves, which are detached from the base upwards, and a seed-bearing frame, but there is no partition wall formed between the placentæ. Ch. majus.--~The majority of the other genera have, like Chelidonium, 2 carpels (lateral and alternating with the sepals: Fig. 391 A) and siliqua-like fruit, thus: Eschscholtzia (perigynous) with a linear, stigma-bearing prolongation extending as far above the placentæ as above the dorsal suture of the carpels; Glaucium (Horn-Poppy); G. luteum, whose extremely long, thin capsule differs from that of Chelidonium by the formation, during ripening, of a thick, spongy (false) replum, which persists when the valves are detached; Sanguinaria with red latex, the 2 petals divided into 8–12 small petals (perhaps by dédoublement); Macleya and Bocconia (1-seeded capsule) with 2 sepals and no petals.--Trimerous flowers are found in Argemone and Platystemon (with a curious fruit, carpels free, and transversely divided and constricted into joints which separate as nut-like portions).--Meconopsis.--Hypecoum (Fig. 393 C) has tri-lobed and three cleft petals, 4 free stamens with 4-locular anthers and a jointed siliqua; it presents a transitional form to the Fumariaceæ, with which order it is sometimes included.~

POLLINATION. Papaver and Chelidonium have no honey, and are without doubt only visited by insects for the sake of the pollen. The anthers and stigmas mature about the same time.--There are 80 species; especially from warm climates. OFFICINAL: Papaver somniferum (Opium-Poppy); the latex of its unripe capsules is obtained by incisions, and dried (opium); it contains many alkaloids: morphine, papaverine, narcotine, thebaine, etc. The oleaginous seeds are also used in the manufacture of oil. Its home is in the East, where it is extensively cultivated. The petals of the Corn-poppy (P. rhœas) are also officinal. Several species are cultivated as ornamental plants.

Order 2. =Fumariacæ= (=Fumitories=). This order differs from the closely allied Papaveraceæ in the absence of latex, a poorer flower, generally transversely zygomorphic (Fig. 393 B), in which case one or both of the outer lateral petals are gibbous, or prolonged into a spur; the stamens are especially anomalous. Sepals =2=, caducous; petals 2 + 2; stamens 2, tripartite; each lateral anther is bilocular (Figs. 393 A, B; 395); gynœceum bicarpellate. The fruit is a nut or siliqua-like capsule. Endosperm.--Herbs with scattered, repeatedly pinnately-divided leaves without stipules, generally quite glabrous and glaucous; the flowers are arranged in racemes with subtending bracts, but the bracteoles are sometimes suppressed.

Dicentra (syn. Dielytra) and Adlumia have a doubly symmetrical flower, with a spur or gibbous swelling at the base of each of the laterally-placed petals (Figs. 393 A, 394). Corydalis has a zygomorphic flower, only one of the lateral petals having a spur, and consequently there is only one nectary at the base of the bundle of stamens, which stands right in front of the spur (Fig. 393 B, 395, 396). The fruit is a many-seeded siliqua-like capsule. ~A peculiarity of the flower is that the plane of symmetry passes transversely through the flowers, whilst in nearly all other zygomorphic flowers it lies in the median line. Moreover, the flower is turned, so that the plane of symmetry ultimately becomes nearly vertical, and the spur is directed backwards.--Many species have subterranean tubers; in these the embryo germinates with one cotyledon, which is lanceolate and resembles a foliage-leaf. The tuber is in some the swollen hypocotyl (C. cava), in others a swollen root (C. fabacea, etc.), which grows down through the precisely similar swollen root of the mother-plant. The sub-genus Ceratocapnos has dimorphic fruits (nuts and capsules) in the same raceme.~ Fumaria differs from Corydalis only by its almost drupaceous, one-seeded nut (Fig. 395).

THE STRUCTURE OF THE FLOWER. Hypecoum among the Papaveraceæ is the connecting link with the Fumariaceæ. The diagram (Fig. 393 C) corresponds both in number and in the relative position of its members with that of most of the other Papaveraceæ (Fig. 391), except that there are only four stamens (with extrorse anthers). In Dicentra (Fig. 393 A), the two central (uppermost) stamens are absent, but each of the two lateral ones are divided into three filaments, of which the central one bears a four-locular anther, and each of the others a two-locular (half) anther. Corydalis and Fumaria stand alone in the symmetry of the flower, differing from Dicentra in having only one of the lateral petals (Fig. 393 B, sp) prolonged into a spur, while in Dicentra both the petals are spurred. This structure has been interpreted in various ways. According to Asa Gray the median stamens are absent in the last-named genera, and the lateral ones are split in a similar manner to the petals of Hypecoum. Another, and no doubt the most reasonable theory (adduced by De Candolle), is: that two median stamens are split, the two parts move laterally, each to their respective sides and become united with the two lateral stamens; this affords a natural explanation of the two half-anthers, and establishes a close relationship to the Cruciferæ. A third interpretation, held by Eichler and others, is as follows: the median stamens are always wanting; when they appear to be present, as in Hypecoum, it is due to the fact that the side portions of the lateral stamens approach each other (as interpetiolar stipules) and coalesce into an apparently single stamen.

130 species; mostly from the northern temperatures.

POLLINATION. Fumaria, with its inconspicuous flowers, has to a great extent to resort to self-pollination. Corydalis, on the other hand, is dependent on cross-pollination; C. cava is even absolutely sterile with its own pollen. Corydalis is pollinated by insects with long probosces (humble-bees, bees), which are able to reach the honey secreted in the spur; as they alight on the flowers they press the exterior petals on one side (Fig. 396 e), so that the stigma, surrounded by the anthers, projects forward; the proboscis is introduced in the direction of the arrow in the figure, and during this act the under-surface of the insect is covered with pollen, which is transferred by similar movements to the stigma of another (older) flower.--Ornamental plants; Dicentra (spectabilis and eximia), Adlumia, Corydalis.

Order 3. =Cruciferæ (Crucifers).= The flowers are regular, ☿; sepals 4, free (2 + 2), deciduous; petals 4, free, deciduous, unguiculate, placed diagonally in one whorl, and alternating with the sepals; stamens 6; the 2 outer are short, the 4 inner (in reality the two median split to the base) longer, placed in pairs (tetradynamia of Linnæus); gynœceum syncarpous formed by 2 (as in the previous order, lateral) carpels, with 2 parietal placentæ, but divided into two loculi by a spurious membranous dissepiment (replum) (Fig. 397). Style single, with a capitate, usually two-lobed stigma, generally commisural, that is, placed above the parietal placentæ (Fig. 397), but it may also be placed above the dorsal suture, or remain undivided. Ovules curved. The fruit is generally a bivalvular siliqua (Fig. 398 B, C), the valves separating from below upwards, and leaving the placentæ attached to the replum; other forms of fruits are described below. The oily seeds have no endosperm (endosperm is present in the two previous orders); the embryo is curved (Figs. 398 E, F; 399, 400).--In general they are herbaceous plants, without latex, with scattered, penninerved leaves, without stipules; the inflorescence is very characteristic, namely, a raceme with the flowers aggregated together at the time of flowering into a corymb, and destitute of both bracts and bracteoles.

Many are biennial, forming in the first year a close leaf-rosette. By cultivation the tap-root can readily be induced to swell out into the form of a tuber (Turnips, Swedes, etc.). Stipules are found indicated by small glands on the very young leaves; in Cochlearia armoracia they are fairly large triangular scales. Stellate hairs often occur. Floral-leaves are occasionally developed. Terminal flowers are never found in the inflorescences. Iberis and Teesdalia have zygomorphic flowers. Subularia (Fig. 403) is perigynous. The 2 external sepals (Fig. 397) stand in the median plane; it may therefore be supposed that there are two bracteoles outside these which, however, are suppressed, and can only in a few instances be traced in the young flower; the two lateral sepals are often gibbous at the base, and serve as reservoirs for the nectar secreted by the glands placed above them; they correspond in position to the external petals of the Fumariaceæ. The 4 petals which follow next arise simultaneously, and alternate with the 4 sepals; if it could be shown that these are merely 2 median petals, which have been deeply cleft and the two parts separated from each other and displaced to the diagonal position, there would be a perfect correspondence with the Fumariaceous flower; then the petals would be followed in regular alternation by the 2 lateral small stamens, the 2 median long stamens, which it has been proved are split into 4 and placed in couples, and the 2 laterally-placed carpels,--in all 6 dimerous whorls. But the formation of the corolla by the splitting of 2 petals does not agree with the development of the flower or bear comparison, and hence the only fact in favour of this theory is the otherwise prevailing correspondence with the Fumariaceæ. Yet it may be observed that in special cases each pair of long stamens clearly enough arises from one protuberance and even later on may be considerably united or entirely undivided (e.g. Vella); in other instances they are quite distinct from the beginning, and it is possible that this latter condition has become constant in the corolla. Lepidium ruderale and others have no corolla. Senebiera didyma has only 2 median stamens. Megacarpæa has several stamens, no doubt by dédoublement, as in Capparidaceæ.--The number of carpels may also be abnormally increased; Tetrapoma barbareifolium has normally 4 carpels with an equal number of placentæ and repla. It is supposed to be a variety of Nasturtium palustre.--The 2–4–8–10 greenish glands, which are found at the base of the stamens, are nectaries, morphologically emergences, and not rudimentary stamens. The forms of fruits are of great systematic significance, see the genera. In some species dimorphic fruits are present, e.g. Cardamine chenopodiifolia which has both ordinary Cardamine-siliquas and 1-seeded siliculas.

The curved embryo appears in five forms, which have systematic importance: 1. To the PLEURORHIZÆ belong those genera whose radicle (with the hypocotyl) lies bent upwards along the edge of the flat cotyledons (Fig. 399); to this group belong Cardamine, Nasturtium, Cheiranthus, Matthiola, Cochlearia, Draba, Iberis, Thlaspi, etc.; diagrammatic transverse section: ◯=.--2. To NOTORHIZÆ belong those whose radicle lies in an upward direction along the back of one of the flat cotyledons (Figs. 400, 413); e.g. Hesperis, Sisymbrium, Lepidium, Capsella, Camelina: ◯‖.--3. ORTHOPLOCEÆ differ from the Notorhizeæ in having the cotyledons folded (not flat) (Fig. 398 E, F); to this belong Brassica, Sinapis, Raphanus, Crambe, etc.: ◯>>.--4. SPIROLOBEÆ: the radicle lies as in the Notorhizæ, but the cotyledons are so rolled together that a transverse section of the seed cuts them twice; Bunias: ◯‖‖.--5. DIPLECOLOBEÆ: the cotyledons are folded forward and backward so that a transverse section cuts them several times; Subularia, Senebiera: ◯‖‖‖.

On germination the cotyledons appear above the ground as green leaves; in the Orthoploceæ they are bilobed, in the Lepidium-species divided.

1. =Silicula, broad replum= (Siliculosæ latiseptæ), valves flat or slightly vaulted, and the replum extends through the greatest width of the silicula (Fig. 404). The seeds are situated in two rows.

◯=: Cochlearia (Horse-radish): the siliqua is nearly spheroid; glabrous herbs, generally with fleshy, stalked leaves, and white flowers.--Draba has an oblong, lanceolate, somewhat compressed silicula; herbs with small rosettes of leaves, most frequently with stellate and long-stalked racemes.--Alyssum and Berteroa are whitish, on account of the stellate hairs; they have a more compressed and round or elliptical silicula. Vesicaria; Aubrietia. Lunaria (Honesty, Fig. 401): very broad and flat silicula with long stalk (the receptacle as in Capparidaceæ).

◯‖: Camelina (Gold-of-pleasure) has a spheroid, pear-shaped siliqua with a small rim passing right round (Fig. 402). Subularia (Awlwort), an aquatic plant with perigynous flower (Fig. 403) and folded cotyledons.

2. =Silicula, narrow replum= (Siliculosæ angustiseptæ), i.e. the replum is much shorter than the arched, more or less boat-shaped valves (Figs. 405, 406, 407).

◯=: Thlaspi (Penny-Cress) has a flat, almost circular silicula, emarginate or cordate, with a well-developed wing round the edge (Fig. 406). Iberis and Teesdalia: the racemes during flowering are especially corymbose, and the most external petals of the outer flowers project radially and are much larger than the other two (the flower is zygomorphic).--Biscutella, Megacarpæa.

◯‖: Capsella (Shepherd’s-Purse) has a wingless, obcordate or triangular silicula (Fig. 407). Lepidium (Pepperwort) has a few–(2–4) seeded, slightly winged, oval silicula. Senebiera has a silicula splitting longitudinally into two nut-like portions; its cotyledons are folded.--~Anastatica hierochuntica (“Rose of Jericho”) is an annual, silicula-fruited, desert plant (Arabia, Syria, N. Africa). After the flowering all its then leafless branches bend together upwards, forming a kind of ball; this spreads out again on coming in contact with water, and the fruits then disseminate their seeds, which germinate very quickly, often in the fruit.~

3. =Siliqua= (Siliquosæ). The fruit is a true siliqua, several times longer than broad. The seeds in most are borne apparently in one row.

◯>>: Brassica (Cabbage). The seeds are placed apparently in one row in each loculus (Fig. 398 C); the style is long and round; the valves have only 1 strong, longitudinal rib.--Melanosinapis (M. nigra, Black-mustard); the style is compressed, two-edged; the valves of the siliqua are one ribbed.--Sinapis (Mustard); quadrangular or flat style (in which in most cases there is a seed) and 3–5 strong, longitudinal ribs on the valves.--Eruca differs from Brassica by the shorter siliqua, broad, sword-like “beak” and seeds in two rows.

◯= (Fig. 399): Cardamine (Bitter Cress) has a long, linear siliqua, with flat, unribbed, elastic valves. The leaves are most frequently pinnatifid or pinnate. ~C. pratensis reproduces by buds formed in the axils of the leaves.~--Arabis (Rock Cress); Matthiola (Stock); Cheiranthus cheiri (Wallflower); Barbarea (Winter Cress) (double-edged, quadrangular siliqua); Nasturtium (N. officinale, Water-cress); the siliqua of the latter genus is in some species short, in others long.

◯‖ (Fig.400): Sisymbrium (Hedge Mustard) the valves of the siliqua are 3-ribbed.--Erysimum; Hesperis; Schizopetalum (with fimbriate petals).

4. =Fruit jointed= (Lomentaceæ). The fruit is divided by transverse walls into as many spaces as there are seeds, and dehisces at maturity, generally transversely, into a corresponding number of nut-like joints (“articulate-siliqua.”)

◯=: Crambe (Kale, Fig. 408). The fruit has only 2 joints. The lower one resembles a short, thick stalk, and is barren, the upper one is spherical, and has 1 seed.--Cakile (C. maritima, Sea-kale); the lower node is triangular, 1-locular, the upper one more ensiform, 1-locular (Fig. 409).

◯>>: Raphanus has a long siliqua, which, in the garden Radish (R. sativus), is spongy and slightly abstricted (Fig. 411), but neither opens nor divides transversely (a kind of dry berry), and which in the Wild Radish (R. raphanistrum) (Fig. 410) is abstricted in the form of a string of pearls, and separates into many joints. ~R. sativus; the “Radish” is formed by the hypocotyl, after the bursting of its external, cortical portions (of which there are generally two patches at the top of the Radish).~

5. =Siliqua indehiscent= (Nucumentaceæ). The fruit is a short, unjointed, unilocular and 1-seeded nut, and the fruit-stalks are often long, slender, and drooping. (Sometimes a thin endosperm is present).--Isatis (Woad) has most frequently an oblong, small-winged nut; ◯‖ (Figs. 412, 413).--Bunias; Neslia.

[The systematic division of this order given above is founded upon that of A. P. de Candolle. Prantl (Engler and Prantl, Nat. Fam.), 1891, adopts a somewhat different system, which may briefly be summarised as follows:--

A. Hairs unbranched or absent; no glandular hairs.

1. THELYPODIEÆ. Stigma equally developed on all sides; style undivided or prolonged above the middle of the carpels, or turned back.--Stanleyinæ; Heliophilinæ.

2. SINAPEÆ. Stigma strongly developed above the placenta; style beaked or two-lobed.

a. Cotyledons arising behind the bend of the embryo.--Lepidiinæ.

b. Cotyledons arising at the bend of the embryo.

α. Only lateral nectaries. Generally a silicula or indehiscent fruit.--Cochleariinæ.

β. Generally a siliqua, more rarely a silicula or transversely-divided or indehiscent fruit. Nectaries generally lateral and median.--Alliariinæ; Sisymbriinæ; Vellinæ; Brassicinæ; Cardamininæ.

B. Hairs collectively or partially branched, very rarely entirely absent; glandular hairs are sometimes also present.

1. SCHIZOPETALEÆ.

2. HESPERIDEÆ. Stigma strongly developed above the placenta; style undivided or prolonged above the placentæ into shorter or longer lobes.

a. Surface cells of the replum, not divided diagonally.--Capsellinæ; Turritinæ; Erysiminæ; Alyssinæ.

b. Surface cells of the replum divided diagonally.--Malcolmiinæ; Hesperidinæ; Moricandiinæ.]

POLLINATION. Honey is secreted by the nectaries mentioned above; but the position of the stamens is not always the most favourable for pollination by insects (in these flowers the honey-seeking insect must touch the anthers with one of its sides and the stigma with the other), and self-fertilisation is common. In some species (Cardamine pratensis) the long stamens turn their anthers outwards towards the small stamens, so that 3 anthers surround each of the two large entrances to the nectaries.

1200 species (180 genera), especially in the cold and temperate parts of the Old World (Europe, W. Asia). Many are weeds in this country, e.g. Wild Cabbage (Brassica campestris), Charlock (Sinapis arvensis), Wild Radish (Raphanus raphanistrum) and others.--The order is acrid and oleaginous. Oil is obtained from many of the oil-containing seeds, especially of the Rape (Brassica napus), Summer-Rape (the oil-yielding cultivated form of the Field-Cabbage) and Camelina. Several are pot-herbs or fodder plants, e.g. Cabbage

(Brassica oleracea) with its numerous varieties: Cauliflower (var. botrytis; the entire inflorescence is abnormally branched and fleshy), Kohlrabi (var. gongylodes, with swollen, tuberous stem), Kale, Red-Cabbage, White-Cabbage, etc.; B. campestris, var. rapifera (Turnip); B. napus, var. rapifera (Swede); Raphanus sativus (Radish from W. Asia), R. caudatus (long Radish); Nasturtium officinale (Water Cress), Lepidium sativum (Garden Cress), and Barbarea præcox (Early Cress); Crambe maritima (Sea-Kkale). The seeds of the following are especially used as spices: (the flour of) Melanosinapis (Black-mustard), and Sinapis alba (White-mustard), which are officinal like the root of Cochlearia armoracia (Horse-radish, E. Eur.). The herbaceous parts of Cochlearia officinalis and danica are medicinal.--A blue dye (woad) is extracted from Isatis.--Ornamental plants: Cheiranthus cheiri (Wallflower), Matthiola (Stock), Iberis, Hesperis, Lunaria, and others (especially from S. Eur.). Sweet-scented flowers are rare.

Order 4. =Capparidaceæ= (=Capers=). The relationship with the Cruciferæ is so close that certain forms are with difficulty distinguished from them. The diagram of the flower is the same in the number and position of its parts, but it differs in the modifications which occur in the development of the stamens. In some genera all 4 stamens are undivided; in others both the 2 median ones are divided as in the Cruciferæ (6 stamens, but not tetradynamous) (Fig. 414); in other genera only 1 of these; in other instances again they are divided into more than 2; and finally the 2 lateral ones also may be found divided, so that indefinite stamens occur (Fig. 415). The bicarpellate gynœceum is unilocular (without replum), but more than 2 carpels may occur. The ovary is elevated on a stalk (sometimes as much as 1 foot in length); also between the stamens and corolla a similar stalk may be found (Fig. 414). The fruit is long and siliquose (Cleome, Polanisia, Gynandropsis), or a berry (Capparis). Endosperm absent. Some have zygomorphic flowers. Gamosepalous calyx and perigynous flowers also occur.--350 species; especially in the Tropics. The majority are trees and shrubs, and they differ also from the Cruciferæ in having distinct stipules present in some species.

“Capers” are the flower buds of the climbing, thorny shrub, Capparis spinosa (Fig. 415), which grows in the Mediterranean.

Family 11. =Cistifloræ.=

The flowers in this family are perfect, regular (except Resedaceæ, Violaceæ), hypogynous, the perianth-leaves free (a few have them slightly united), æstivation most frequently imbricate; they are eucyclic in the andrœcium, and most frequently in the other parts, and generally 5-merous with S5, P5, A5 + 5, G3, but other numbers also occur; several have indefinite stamens, but the stamens arise (where the development is known) in centrifugal order and are arranged, often very distinctly, in bundles; in other words, the large number of stamens is formed by the splitting of a small number (most frequently 5); a true spiral arrangement is never found. Gynœceum syncarpous, multicarpellary (Dilleniaceæ and a few Resedaceæ are apocarpous), most frequently the number of carpels is 3, forming a unilocular ovary with parietal placentæ, but parallel with this, multilocular ovaries, with the ovules placed in the inner angle of the loculi, are also found, and a few genera have a free, centrally-placed placenta. The fruit is most frequently a capsule. The dehiscence is never with a “replum,” i.e. the persistent frame of the placenta, as in the family Rhœadinæ. One half of the orders has endosperm (Violaceæ, Cistaceæ, Droseraceæ, Bixaceæ, Ternstrœmiaceæ, etc.), the other has no endosperm (Resedaceæ, Hypericaceæ, Elatinaceæ, Tamaricaceæ, etc.); some have a curved, the majority a straight embryo. ~The family is scarcely quite natural; in the future the orders will probably be arranged differently.~

Order 1. =Resedaceæ (Mignonettes).=--Herbs or small shrubs with spirally-placed leaves and very small, gland-like stipules (as in Cruciferæ); the ☿, hypogynous flowers are zygomorphic, and arranged in racemes or spikes typically without bracteoles. The zygomorphic structure is produced by the greater development of the posterior side of the flower, especially the petals and the nectary (“disc,” in Fig. 416 d) which is situated between the petals and stamens; in general there are 5–8 free sepals and petals, the latter consisting of a large scale-like sheath with a fimbriated blade (see Fig. 416); stamens numerous; carpels 6–2 united together; ovary unilocular with parietal placentæ, but the cavity of the ovary is not closed at the top. In Astrocarpus the gynœceum is apocarpous. The fruit is most frequently a capsule; the seeds are reniform, without endosperm, and the embryo is curved.

This order connects the Rhœadinæ with the Cistifloræ. It is closely allied to the Rhœadinæ by its external appearance, even by the smell and taste, the parietal placentation, structure of the seeds, the inflorescences, etc., whilst by the irregular flowers and the disc placed at the posterior side of the flower, it is allied to Capparidaceæ, but differs from this order in not having its characteristic number (2–4) and by the very different mode of dehiscence of the fruit, etc. It differs from the other orders of this family chiefly in the fact that the number of the perianth-leaves is not constantly 5. In Reseda luteola both the calyx and corolla appear to be 4-leaved, because the posterior sepal is suppressed, and the 2 posterior petals are united. Where there are 10 stamens, they stand in 2 whorls, i.e. in front of the sepals and petals; if there are several, their position depends upon the splitting.--Astrocarpus is remarkable for its apocarpous fruit and the position of the ovules on the dorsal suture of the carpel.

The yellow, flat disc at the back of the flower serves as a nectary, the honey being protected by the lobes of the petals. If pollination by insects is not effected, then self-pollination may take place, at all events in R. odorata.

45 species; the majority in the Mediterranean and in Persia. Reseda odorata (from Egypt) is cultivated on account of its sweet scent; R. luteola (“Dyer’s Weed”) yields a yellow dye.

Order 2. =Droseraceæ (Sundews).= Herbs, chiefly living on moors or in water, and whose leaves are adapted to catch and digest small animals. With regard to the flower, they are closely allied to the Violaceæ, especially to those with regular flowers. Drosera (Sundew) has a long-stalked scorpioid cyme with regular, ☿, hypogynous flowers, 5-merous as in Viola. S5, P5, A5, G3 (in a syncarpous gynœceum, with free, bifid styles and basal or parietally-placed ovules in the unilocular ovaries). The capsule opens also as in Viola, but, among other differences, the styles are free, the seeds very small, and surrounded by a loosely lying, thin shell. ~Drosera has radical, long-stalked leaves with the blade (Fig. 417) covered by numerous strong glandular hairs, placed on the edge and in the middle; when small animals are caught by these hairs, the latter and the entire blade close slowly over them dissolving and absorbing all the digestible matter as nourishment.~

Dionæa muscipula (Fly-trap; N. Am.) has the same appearance as Drosera, but the leaves are constructed as in Fig. 418. The stalk is flat and winged, the blade small, circular, with powerful, pointed teeth along the edge, and on its surface are 6 small bristles (A), which are very sensitive. When these are touched the blade quickly closes, folding along the midrib (B, C) and imprisoning the irritating object, the teeth round the edges fitting like the teeth of a trap. If it happens to be an insect or similar body, a digestive fluid is secreted which, like the gastric juice, dissolves the digestible portions. Aldrovandia vesiculosa (Central and S. Europe) captures small aquatic animals in a similar manner; it is a floating, aquatic plant, the two halves of its leaves also close together when irritated (Fig. 419).--Drosophyllum.

About 110 species; most of them in the temperate regions.

Orders 3 and 4. =Sarraceniaceæ and Nepenthaceæ.= These two orders are perhaps most closely allied to the Droseraceæ and agree with these, among other things, in the manner of taking nourishment. Like the Droseraceæ they absorb nitrogenous food from dissolved animal matter by means of their leaves, which are specially constructed both to catch, to retain, and to digest any small animals which may be caught. The SARRACENIACEÆ are North American marsh-plants (10 species) which have pitcher-like leaf-stalks, in the cavity of which a fluid (with properties approaching those of gastric juice) is secreted, and which bear at the apex a small, lid-like blade; these leaf-stalks are the catching and digestive organs.--Sarracenia, Darlingtonia.

NEPENTHACEÆ has only 1 genus, Nepenthes (the Pitcher-plant; about 35 species), especially found in tropical E. Asia; the majority are climbing shrubs. The leaf-stalks are twining organs, and terminate either simply in a tendril, or in addition to this, with a pitcher-shaped body (which in some species may be as much as a foot in length) on whose upper edge a lid-like structure is found (Fig. 420). In this pitcher, as among the Sarraceniaceæ, a fluid is secreted which is able to digest the animals captured (sometimes rather large) and which corresponds in some degree to the gastric juice.

Order 5. =Violaceæ (Violets).= The flowers are ☿, and generally zygomorphic, hypogynous, with S5, P5, A5, G3 (Fig. 421). The stamens are closely applied to the ovary, they have a very short filament, and at their summit generally a membranous appendage formed by the prolongation of the connective (Fig. 422 g). The ovary is unilocular with 3 parietal placentæ; style undivided (Fig. 422 B). The fruit is usually a 3-valved capsule, opening along the dorsal sutures (Fig. 423). Embryo straight; endosperm fleshy (Fig. 425).--Many are herbaceous plants (e.g. Viola), but in the Tropics shrubs are also found (e.g. Ionidium); a few are lianes; the leaves are scattered, with stipules, and involute in the bud.

Viola. The sepals are prolonged backwards beyond the point of insertion (appendiculate); the corolla is polypetalous, descending imbricate, and zygomorphic, its anterior petal being larger than the others and provided with a spur (Fig. 421). The 2 anterior of the 5 almost sessile stamens are provided with a spur-like nectary, which protrudes a considerable distance into the petaloid spur (Figs. 421, 422 n, sp). The style is club-like, and bears the stigma in a groove on the anterior side (Fig. 422 st). ~Herbs with rhizomes, or annuals; flowers solitary. V. odorata, canina, etc., have cleistogamic flowers which produce fruit in addition to the large, coloured (violet) flowers. The Pansy (V. tricolor) has large flowers adapted for insect-pollination, and also smaller, less conspicuous ones designed for self-pollination. The stigma, as in Fig. 422 A, st, and B, is situated on the anterior side of the stylar-head, immediately in front of the channel leading down to the spur (sp); below it is situated a valve, easily covered with pollen when the proboscis of an insect is introduced into the spur, but which closes upon its withdrawal; cross-pollination is thus secured.--The sweet-scented V. odorata is visited by the honey-bee, which insures cross-pollination, and in the absence of insect visits it effects self-fertilisation by cleistogamic flowers. The conspicuous but scentless V. tricolor, var. vulgaris, is less frequently visited by insects (humble-bees). In V. silvatica and V. canina the pollen is carried on the head or proboscis of the honey-sucking bee.--The fruits of V. odorata bury themselves slightly in the soil. In the others the fruits are raised above the ground; the 3 boat-shaped valves close together along the central line, and eject the seeds, one by one, with much violence, so that they are thrown to a great distance.~

The Alsodeia-group has regular or almost regular flowers. Gamopetalous corollas are found in Paypayroleæ. Sauvagesieæ differs the most by its regular corolla, and 5–∞ free or united staminodes.

250 species; especially in the Tropics.--The Ionidium-species are used as ipecacuanha. A number of Viola-species are cultivated as garden plants, especially V. odorata (sweet-scented Violet) and V. tricolor, which have a large number of varieties.

Order 6. =Frankeniaceæ.= A small order with doubtful relationships. Perennial herbs or shrubs; beach plants with nodose stem. Sepals united, petals free. Unilocular ovary, with 3–4 parietal placentæ. Fruit a capsule. Embryo straight, endospermous. Especially in S. Europe, Africa, on the shores of the Mediterranean and Atlantic.

Order 7. =Tamaricaceæ (Tamarisks).= To this order belong only Tamarix and Myricaria. They are shrubs of a cypress- or heather-like appearance, as the scattered leaves are very small, sessile, scale-like or linear, adpressed, entire, and usually glaucous, and the branches are slender and whip-like. The flowers are borne in small spikes or racemes, and are small, reddish or whitish, regular, ☿, hypogynous and polypetalous; formula S5, P5, A5 + 0 (Tamarix, which often has stipular teeth at the base of the filaments), or A5 + 5 (Myricaria, in which the stamens are united at the base); the number 4 may appear instead of 5, but in either case there is usually a tricarpellate gynœceum, which is unilocular and has either parietal placentæ (Myricaria) or a small basal placenta (Tamarix); 1 trifid style, or 3 styles. Capsule dehiscing along the dorsal suture, and resembling the Willows in having a unilocular ovary with numerous woolly seeds; but the seed-wool in this case is borne on the chalaza, and may be attached to a long stalk.--Some Tamarix-species shed part of their branches in the winter.--40 species; North Temperate, on the sea-shores or steppes, especially in Asia. Ornamental shrubs: Myricaria germanica, and Tamarix gallica.

Order 8. =Cistaceæ.= Shrubs or herbs, natives especially of the Mediterranean region. Flowers generally in raceme-like scorpioid cymes, regular, ☿, hypogynous; sepals 5, free, twisted in the bud, of which the two outer are generally much smaller than the others; petals 5, free, twisted in the bud (in the direction opposite to the sepals), fugacious; stamens numerous; gynœceum syncarpous, carpels usually 3–5, style simple, ovary unilocular, with parietal placentation (seldom divided into loculi, with axile placentation). The ovules are orthotropous in opposition to some of the other orders of this family. The capsule dehisces along the dorsal sutures; embyro curved. The leaves are simple, undivided, generally opposite and stipulate.--~They are Violaceæ with regular flowers, numerous stamens, and curved embryo. The numerous stamens are in reality only one or two 5-merous whorls, divided into a large number of stamens; these are formed, therefore, in descending order, like the lobes of many compound foliage-leaves.~

Helianthemum (Rock-Rose), has 3 carpels.--Cistus has 5 (-10) carpels.

About 70 species; temperate climates, especially about the Mediterranean. The resin of the Cistus-species has been used medicinally (ladanum).

Order 9. =Bixaceæ.= This order is closely allied to the Cistaceæ and Ternstrœmiaceæ; like these it has regular, 5-merous, hypogynous flowers with numerous stamens, unilocular ovary and parietal placentæ; sometimes unisexual flowers; it differs in having anatropous ovules, in the æstivation of the sepals, etc. All species (about 180) are trees or shrubs, with scattered, simple leaves, which usually have stipules, and are occasionally dotted with pellucid oil-glands.--Bixa orellana (Trop. Am.) is the best known species; it has a 2-valved capsule; the seeds are enclosed in a shiny red, fleshy testa, which contains the well-known orange or yellow dye, annatto.

Order 10. =Dilleniaceæ.= Gynœceum usually apocarpous, seed arillate. The flower has most frequently S5, P5, and compound stamens (one or more bundles); sometimes irregular. 200 species; Tropical; woody plants, many lianes.--Dillenia, Candollea, Pleurandra, Davilla, etc.

Order 11. =Elatinaceæ= (=Water-worts=). About 25 species belong to this order; especially in temperate climates. They are small, creeping, rooted, aquatic plants, with opposite or verticillate leaves and stipules. The flowers are solitary or situated in small dichasia in the leaf-axils, they are small, regular, ☿, hypogynous, with free petals, the same number in all 5 whorls (Sn, Pn, An + n, Gn), 3-merous (e.g. Elatine hexandra), 4-merous (e.g. E. hydropiper), or 5-merous (Bergia); the corolla-stamens are sometimes suppressed; petals imbricate without being twisted; the ovary is 3–4–5-locular, with 3–4–5 free styles; the capsule dehisces septicidally. The seeds are orthotropous or curved, often transversely ribbed, endosperm wanting. The order is most nearly allied to Hypericaceæ, whose primitive form it appears to represent.

Order 12. =Hypericaceæ= (=St. John’s-worts=). This order is recognised by its always opposite or verticillate, simple, and entire, penninerved leaves, without stipules, and usually dotted with pellucid glands; by the always ☿, regular, hypogynous flowers in a cymose inflorescence; the generally 5-merous calyx and corolla, with sepals and petals free; the stamens 3–5, numerously branched (Figs. 426, 427); and the gynœceum, 3–5-carpellate, styles usually free. The ovary is 3–5-locular, or unilocular with 3–5 parietal placentæ. Fruit a capsule (dehiscing septicidally) or berry. Endosperm absent.

The inflorescence is a dichasium or helicoid cyme. The structure of the flowers is the same as that of the foregoing orders: S5, P5; succeeding these in some cases are two 5-merous whorls of stamens in regular alternation, of which the inner is epipetalous; but the outer whorl is only represented by 5 small scales (Fig. 427), or is altogether absent (Hypericum calycinum, H. hircinum), and the inner divided into numerous stamens, that is, these 5 stamens are so deeply divided that 5 epipetalous groups bearing anthers are found (as in the Cistaceæ); in other cases the flower becomes 3-merous after the petals, stamens 3 + 3 following in regular alternation (Figs. 426, 427), the outer whorl of stamens in these cases is also present as staminodes (Fig. 427), or may be altogether suppressed. Carpels 3–5. The petals are often twisted in the bud, and are then oblique.

Hypericum. Some species have a square stem; in these cases the leaves are placed opposite the edges. Fruit a capsule.--Vismia has a berry.--~The flowers of Hypericum have no honey, and supply only pollen; self-pollination often takes place.~

About 240 species; the tropical ones being often shrubs or trees; the others generally perennial shrubs.--Hypericum, St. John’s-wort, contains a resinous, red matter, which can be extracted with alcohol. The American gamboge is the dried sap of species of Vismia.

Order 13. =Guttiferæ=, or =Clusiaceæ=. Closely allied to the Hypericaceæ and Ternstrœmiaceæ. Leaves opposite or verticillate. The flowers are often unisexual; stamens united; the gynœceum has most frequently a sessile, radiating or shield-like stigma.

370 species; chiefly in the Tropics (Am.). They are principally woody plants and their bark contains a yellow gum resin, “gamboge,” which is extracted from Garcinia morella (E. Ind.) and others. Mangosteen (Garcinia mangostana S.E. Asia), and Mammea americana (W. Ind.), have very delicious fruits. To this order also belong Platonia insignis, Pentadesma butyracea (the Butter-tree), Clusia, Calophyllum, Cataba, etc.

Order 14. =Ternstrœmiaceæ.= Trees and shrubs with scattered, simple, and often more or less leathery, evergreen, penninerved leaves, without stipules (Fig. 428). The two most important genera are: Camellia and the closely allied Thea (by some authorities these are united into one genus). The flowers are regular, hypogynous, and situated singly on very short stalks. A number of green floral-leaves are placed below the calyx and gradually pass over into the sepals, and the leaves (5–6) of the calyx again gradually pass over into the corolla (this being especially marked in Camellia), of which the number of leaves varies (5, 6, 7 and upwards); the calyx and the corolla are acyclic or eucyclic; the petals are slightly united at the base; stamens numerous in many whorls, the external ones are arranged in bundles and united with the petals as in the Columniferæ; gynœceum syncarpous; styles often free nearly to the base; ovary 3–5-locular, ovules numerous in each loculus. The fruit is a woody capsule.--~Other genera show more distinctly than these the same structure as in the preceding orders, namely: S5, P5, A5 + 5, of which the calyx-stamens are often suppressed, and the petal-stamens divided into numerous stamens.--Kielmeyera (S. Am.)~

260 species; especially in the Tropics (E. Asia, Am.) The leaves of Thea chinensis (or Camellia thea), the Tea-tree (E. Asia), are cultivated for the well-known “tea,” and contain theine: the best are the young, still hairy leaves, of greyish colour; there are many varieties. Ornamental plants, Camellia japonica and Actinidia.

Closely allied to this order are: Order 15. =Rhizoboleæ= (with enormously large hypocotyl--hence the name), and Order 16. =Marcgraviaceæ= (partly epiphytes, with dimorphic leaves and cup- or helmet-like, coloured, honey-secreting floral-leaves, which serve to attract insects).

Order 17. =Dipterocarpaceæ.= This order has taken its name from the large wings attached to the fruits in Dipterocarpus (the wings being largely developed sepals); trees and shrubs from Trop. Asia. 180 species. Camphor ready prepared is found in the stem of Dryobalanops camphora. Hopea; Vateria.

Family 12. =Gruinales.=

The flowers are hypogynous, ☿, polypetalous, usually regular (except Pelargonium, Tropæolaceæ, Balsaminaceæ) and throughout 5-merous: S5, P5, A5 + 5, or 5 + 0, G5 (epipetalous). The stamens soon fall off and are obdiplostemonous, often united at the base (monadelphous); the corolla-stamens are in some completely suppressed (e.g. Balsaminaceæ, Fig. 438), in others reduced to teeth (Linum, Fig. 431; Erodium). The Tropæolaceæ have 3 carpels and only 8 stamens (Fig. 437). Ring-like nectaries are not present, but at most only glandular bodies, borne outside the base of the stamens. Ovaries many-locular. The ovules as a rule are pendulous, with the micropyle directed outwards (Fig. 431, B), and the radicle therefore also points outwards. Usually herbs. Related to the Columniferæ.

Order 1. =Oxalidaceæ.= Most of the species are herbs with rhizomes; the leaves are stalked, compound, with entire leaflets which are folded and bent backwards in the bud (and in the sleep position), exstipulate; some species have sensitive leaves. The flowers (Fig. 429) are regular, and have S5, P5, which are twisted to the left or right in æstivation, A5 + 5, all united at the base (monadelphous), gynœceum 5-carpellate, styles 5 free, stigmas capitate, ovary 5-locular, ovules numerous. The fruit is a capsule opening with clefts on the dorsal sutures through which the seeds are ejected, while the fleshy, external layer of the testa springs off elastically. Embryo straight. Endosperm.

Oxalis (Wood-Sorrel). Leaves digitate. Species also occur with phyllodia, i.e. leaf-like petioles placed vertically without lamina; a few have pinnate leaves. The flowers are situated singly or in dichasia, and unipared scorpioid cymes. The pollination is effected by insects. Some species are trimorphic (long-, short-, medium-styled flowers) and some, e.g. O. acetosella, have cleistogamic flowers in addition to the ordinary ones. Glands are found on the outer side of the corolla-stamens or of all the stamens. O. tetraphylla and others have adventitious edible roots, resembling tap-roots.--Averrhoa is a tropical tree, with berries and pinnate leaves.

235 species (205 belong to Oxalis); chiefly in S. Africa and Trop. America.--Oxalate of potash is contained in the leaves of Oxalis.

Order 2. =Linaceæ.= Herbs with scattered or opposite, sessile, simple, small, entire leaves, without (rarely with small) stipules. The flowers (Fig. 430) are regular, 5- or 4-merous. Petals are free, twisted, quickly falling off. Stamens united at the base; the petal-stamens are either reduced to teeth (Fig. 431 A, m) or entirely suppressed. Styles free. The (5–4) epipetalous loculi of the ovary are incompletely halved by false divisional walls, each half contains one ovule (Fig. 431 C). The fruit is a spherical capsule, dehiscing along the divisional wall (Fig. 432); the 10 (-8) seeds have a straight embryo and very slight endosperm (Fig. 433).

Linum (Flax) has 5-merous flowers. ~The main axis terminates in a flower; and the succeeding branching is cymose, or unipared scorpioid branching by unilateral development, and the flowers in consequence of the vigorous sympodial development of the lateral axis (and also by the leaves being displaced and pushed aside), assume a position apparently lateral (i.e. racemose) without bracts; each branch of the sympodium generally has 2 leaves. The testa is shining and smooth when dry, but its external cellular layer becomes mucilaginous in water.~--Radiola has a 4-merous flower. It is a small herb with opposite leaves, and regular, dichasial branching.

The anthers and stigmas in L. catharticum and usitatissimum develop simultaneously, and cross-pollination as well as self-pollination takes place. L. grandiflorum, perenne, and others, are dimorphic (short-and long-styled). There are 5 nectaries outside the stamens.

130 species; Linum and Radiola are native genera.--L. usitatissimum is extensively cultivated in Europe (especially in Russia and Belgium), N. America and elsewhere (its home no doubt being Asia), partly on account of the oil (linseed oil) which is extracted from the seeds, and partly on account of the bast of the stem, which has very thick-walled cells. The seeds and oil are OFFICINAL. The species cultivated in ancient times was L. angustifolium. Several species are cultivated as ornamental plants.

Order 3. =Geraniaceæ.= The majority are herbs with dichasial branching, and scattered or opposite, stalked, palminerved (rarely penninerved) leaves with small stipules. The flowers are regular (except Pelargonium) and 5-merous, with 10 or 5 stamens, which are slightly united at the base. Nectaries alternate with the corolla-stamens. The ovary is most frequently 5-locular, deeply 5-grooved, and bears 1 well developed style (“beak”), which towards the apex divides into 5 branches bearing stigmas; ovules 1 in each loculus, pendulous or ascending. The 5 carpels become detached from one another when ripe, and bend or roll back (Fig. 434) or become spirally twisted in the upper “beak-like” part (Figs. 435, 436), whilst a central column (septal column) persists; each carpel, in consequence, remains either closed, and the fruit is a 5-merous schizocarp whose nut-like lower portion, containing the seed, is forced into the ground, thus burying the seed by the movements of the spirally-twisted, hygroscopic “beak” (Figs. 435, 436); or it opens along the ventral suture, so that the seeds may fall out, and it is then a 5-valved capsule, with septicidal dehiscence (Fig. 434) and the rolling up often takes place so suddenly and violently that the seeds are shot out to considerable distances. The embryo is usually green and curved, and the cotyledons are folded; endosperm is wanting.

Geranium (Crane’s-bill) has 5 + 5 stamens,and a septicidal capsule; the carpels most frequently remain suspended from the apex of the column (Fig. 434). The leaves are most frequently palminerved. The flowers are situated solitarily or 2 together (2-flowered scorpioid cyme).--Erodium (Stork’s-bill); inflorescence a many-flowered unipared scorpioid cyme, stamens 5 + 0 (petal-stamens are wanting), and fruit a schizocarp whose carpels become detached; their beaks are hairy on the internal surface and twist themselves spirally (Fig. 436). The umbellate inflorescences are composed of multiflowered scorpioid cymes. The leaves are often penninerved.--~The most primitive type is represented by Biebersteinia: S5, P5, A5 + 5, G5 (ovaries free, and styles united above); fruit 5 small nuts. The most advanced type is Pelargonium, which has zygomorphic flowers, the posterior sepal being prolonged into a spur which becomes adnate to the peduncle; the petals are unequal in size; some of the petal-stamens are often wanting. (Erodium may be slightly zygomorphic).~

POLLINATION. The large-flowered Geranium-species are protandrous, e.g. G. pratense (one whorl of stamens opens first, and then the other, and succeeding these the stigmas, after shedding the pollen the stamens bend outwards); the small-flowered are also adapted, with various modifications, for self-pollination.--470 species; moderately hot climates, especially S. Africa.--Several Pelargonium-species, with numerous varieties, are ornamental plants (from S. Africa).

Order 4. =Tropæolaceæ.= Herbaceous, juicy plants which have scattered, long-stalked, peltate leaves without stipules, and often climb by their sensitive petioles. The flowers are situated singly in the axils of the foliage-leaves on long stalks, and are zygomorphic, the receptacle under the posterior sepal being prolonged into a spur; there are also differences between the posterior and anterior petals, the 2 posterior petals situated on the border of the spur being perigynous, and the edge of the anterior petals adjoining the claw fringed. After the 5 sepals (which are more or less coloured) and the 5 petals, follow 8 stamens (as the 2 median ones are suppressed, one from each whorl) and a gynœceum formed of 3 carpels; in each of the 3 loculi of the 3-grooved ovary is 1 ovule. The fruit is a schizocarp and divides into 3 1-seeded, drupe-like fruitlets, which do not (as in the Geraniaceæ) leave any pronounced column between them. Endosperm is wanting. The cotyledons are thick and sometimes slightly coalescent. ~Tubers often occur.~

Tropæolum.--About 40 species; all from America.

POLLINATION.--The spur is the receptacle for the nectar; the flowers are protandrous; the anthers open first, and one by one take up a position in front of the entrance to the spur, resuming their original position when the pollen is shed; the stigma finally takes their place after the filaments have bent backwards.--These plants have an acrid taste (hence the name “Nasturtium,” “Indian Cress”), on which account the flower-buds and young fruits of T. majus are used as capers. Some species are ornamental plants.

Order 5. =Balsaminaceæ.= Herbaceous, chiefly annual plants with juicy, brittle stems, so transparent that the vascular bundles may be distinctly seen. The leaves are simple, usually scattered, penninerved and dentate; stipules are wanting, but sometimes large glands are present in their place at the base of the petioles. The flowers are strongly zygomorphic; of their five 5-merous whorls the petal-stamens are suppressed (S5, P5, A5 + 0, G5); the sepals are coloured, the 2 anterior ones (Fig. 438 3, 5) are very small or entirely suppressed, the posterior one is very large and elongated into a spur, and the 2 lateral ones pushed forward; sometimes the weight of the spur turns the flower completely round, so that the posterior leaves assume an anterior position; apparently only 3 petals, since the lateral and the posterior petals become united in pairs, and the anterior is larger and differently shaped; the 5 stamens have very short and thick filaments united at the base, and their anthers finally adhere together and remain in this condition, covering over the gynœceum; the filaments ultimately rupture at the base, and the entire anthers are raised on the apex of the gynœceum as it grows up. The gynœceum has a sessile stigma and a 5-locular ovary. The fruit is a capsule which, on maturity, opens suddenly when irritated, dividing into valves from the base upwards, and as the 5 valves roll up elastically, the seeds are shot out on all sides to considerable distances; a central column persists (Fig. 439). The embryo is straight, and without endosperm.

Impatiens; in Europe only I. noli-me-tangere. 225 species; especially from Asia. Several species have two kinds of flowers: small, cleistogamic, but fertile; and large, coloured flowers, which in I. balsamine (ornamental plant, E. Ind.) are protandrous and pollinated by hive-and humble-bees, as they suck the honey from the spur.

Order 6. =Limnanthaceæ.= The flowers are regular and differ from all the other orders in the family by having the carpels not in front of the petals, but in front of the sepals (which are valvate), and further, the loculi are nearly free individually, but with a common gynobasic style; the ovules are ascending and apotropous (anatropous with ventral raphe). The fruit is a schizocarp, with nut-like cocci.--Limnanthes (4 species; N. Am.) perhaps belongs to another family.

Order 7. =Humiriaceæ.= Trees and shrubs; about 20 species; Trop. Am.

Family 13. =Columniferæ.=

The chief characteristics of the orders belonging to this family are the ☿, regular, generally 5-merous, hypogynous flowers with 5-merous calyx, sepals united and valvate in the bud; petals 5, free (often twisted in the bud); stamens ∞ e.g.: 10, in two whorls, but one of these is more or less suppressed, often altogether wanting, or replaced by 5 staminodes, while the other (inner whorl) is generally divided more or less deeply into a large number of anther-bearing filaments. The filaments too (except Tiliaceæ) are united into a tube, which, especially in the Malvaceæ, forms a long column in the centre of the flower, surrounding the gynœceum (Figs. 445, 448); in this case, which is the most pronounced, the filaments are united into one bundle (monadelphous), in other instances, polyadelphous. The number of carpels varies greatly (2 to about 50), but they are nearly always united and form a syncarpous multilocular gynœceum.--The vegetative characters also closely agree, the leaves are always scattered and generally stipulate; all the green portions very often bear stellate hairs, and the bark in all the 3 orders is rich in tough bast. Mucilage is often present in cells or passages.--This family is connected with the Ternstrœmiaceæ, from which it is very hard to draw a sharp line of demarcation, and it is also allied to the Cistaceæ and to the Gruinales.

Order 1. =Sterculiaceæ= (including Buettneriaceæ). This is, no doubt, the least modified order, and one in which the stamens occur undivided. Obdiplostemonous. The 10 stamens in two whorls are most frequently united at the base into a short tube, and have 4-locular, extrorse anthers. The calyx-stamens are nearly always simple, tooth-like staminodes, situated on the edge of the tube, or are entirely suppressed. The same relation is found, for instance, in the Ampelidaceæ and Rhamnaceæ, namely 5 stamens in front of the 5 petals; not infrequently the 5 stamens are doubled (Fig. 441). Unisexual flowers are found in Sterculia, Cola, Heritiera. The corolla is often wanting, or developed in an unusual manner. Each loculus of the ovary (generally 5) always contains more than one ovule. Fruit a capsule. Androgynophore often present (Helicteres; Sterculia, etc.).

Hermannia, Mahernia, Melochia, etc., have flat petals with twisted æstivation; 5 undivided stamens, which usually are but slightly united at the base, and most frequently, without staminodes. Thomasia; Helicteres; Sterculia (free follicles).--Theobroma, Rulingia, Buettneria, Commersonia, Guazuma, etc., have petals concave at the base, and terminating in a limb abruptly bent back, and at the boundary between them most frequently ligular outgrowths, as in certain genera of the Caryophyllaceæ; stamens 5–15–∞, anthers at the edge of a short tube and 5 linear staminodes (Fig. 441).--The Cocoa-tree (Theobroma), (Fig. 440) bears large, reddish-yellow, berry-like fruits, resembling short cucumbers, but ultimately becoming leathery to woody; in each of the 5 loculi are 2 (apparently only 1) rows of horizontal, oily seeds, as large as almonds. Cotyledons large, thick, and irregularly folded. Endosperm absent (Fig. 442).

49 genera, with about 750 species; almost entirely confined to the Tropics; none in Europe or in N. Asia.--The seeds of the Cocoa-tree (T. cacao, bicolor, glaucum, etc., natives of Trop. Am., especially north of the Equator) are used for chocolate and are also officinal (“Cocoa-beans,” “Cocoa-butter,” “Oil of Theobroma”). Theobromine. Cola acuminata, Africa.

Order 2. =Tiliaceæ.= This differs from the other orders of the Columniferæ chiefly in the stamens being entirely free from each other, and also divided into many filaments, as far as the base, or at all events very far down, so that the flower appears to have numerous stamens or to be slightly polyadelphous (Fig. 443); in addition to this, it may be observed that the anthers are 4-locular and introrse. In Luehea the groups of stamens alternate with the petals. In a few genera (Corchorus, Triumfetta) 10 free and single stamens are found in 2 whorls; but, in the majority, groups of free stamens in separate bundles. The stamens are more or less united in Apeiba, Luehea. Style simple. Ovary 2-locular. The ovules are pendulous; raphe turned inwards. The calyx readily falls off; the æstivation of the entirely free petals is slightly imbricate (not twisted).

Tilia (Figs. 443, 444). Calyx and corolla 5-merous; the 5 staminal leaves (opposite the petals) divided as far as the base into a large number of stamens which are free or united into groups; gynœceum with 5 loculi in the ovary (opposite the sepals); there are 2 ovules in each loculus, though the ovary ripens into a 1-seeded nut, which is not detached from the axis of the inflorescence, but is carried away by the wind, whirling round and round, its large-winged bracteole serving as a parachute (Fig. 443).--~Only trees, with alternate, obliquely heart-shaped and dentate leaves; stellate hairs, as in the other Columniferæ, are often present. The terminal bud of the branch always fails to develop, and the growth is then continued sympodially by the uppermost axillary buds. The INFLORESCENCE (Figs. 443, 444) is a 3–7-flowered dichasium (Fig. 444 t, d, e), which is developed in the axil of a foliage-leaf (Fig. 444). The first of its 2 bracteoles (a) is large, thin, leaf-like, and united with the inflorescence, the lower portion of which forms a broad wing, its so-called “bract”; the second bracteole (b), on the other hand, remains scale-like, and supports a winter foliage-bud covered with bud-scales which thus is situated at the base of the inflorescence, and is a bud of the 2nd order, in relation to the vegetative shoot. This bud is always found beneath the inflorescence on the branch placed horizontally, and the winged bracteole is always found above it, a relation which is connected with the fact that the 2 rows of shoots on the sides of a branch are antidromous with regard to each other.--The dichasium itself (Fig. 444) terminates with the flower (t); it has 3 floral-leaves (c, d, e), which soon fall off; c is barren: the other two bear flowers, or few-flowered dichasia, or unipared scorpioid cymes (indicated in the figure).--The foliage-leaves are folded in the bud upon the median line (1, 2, 3 in Fig. 444 are foliage-leaves with their 2 stipules), the inner half is broader than the outer, and after unfolding is turned away from the mother-axis (the position of the new inflorescences and vegetative buds is indicated in their axils on the figure).--The cotyledons on germination appear above the ground as large, lobed leaves.~

Of the other genera some have a bell-shaped, gamosepalous calyx, some have no corolla, the anthers of some open at the apex (Aristotelia, Elæocarpus, etc.), the majority have a capsule, some have berries, or drupes, some separate into fruitlets, etc.--Corchorus, Triumfetta (nut, with hooked bristles), Luehea, Apeiba, etc. Sparmannia is an African genus; 4-merous flowers; fruit a warted capsule; filaments numerous and sensitive to touch, the external ones are without anthers and moniliform above. The plant is covered with numerous soft and stellate hairs, and at the apex of the branches bears several cymose umbels.

POLLINATION in Tilia is effected by insects, especially bees and Diptera, which swarm round the tree tops, allured by the numerous strongly-scented flowers and the easily accessible honey (formed in the hollow sepals). As the flowers are pendulous, the nectar is protected from ruin; and, in addition, the inflorescence is more or less concealed beneath the foliage-leaf. Self-pollination is impossible, on account of protandry.--About 470 species (nearly all trees and shrubs); especially in the Tropics, only a few being found in the temperate, none in the polar regions, or in high mountainous districts.--The inflorescence of the native species of Tilia is medicinal. The wood is used for charcoal.--The majority are used for timber, and for the sake of the bast (“Bast,” “Jute,” the bast of Corchorus textilis, Luehea, and others).

Order 3. =Malvaceæ= (=Mallows=). The plants are easily recognised by the scattered, simple, palminerved, most frequently lobed, stipulate leaves, folded in the bud; the perfect, regular, hypogynous flowers, with gamosepalous, persistent, 5-merous calyx with valvate æstivation; the 5 petals twisted in the bud and united with one another at the base, and by the 5 apparently numerous stamens (Figs. 445, 448), with the filaments united into a tube, with reniform bilocular anthers opening by a crescentic slit (in 2 valves). Carpels 3–∞ united into one gynœceum; the embryo is curved and the cotyledons are folded (Figs. 447, 451); endosperm scanty, often mucilaginous.--Most of the plants belonging to this order are herbs, often closely studded with stellate hairs. The leaves are most frequently palmatifid or palmatisect.

An epicalyx is often found formed by floral-leaves placed close beneath the calyx, in some 3, in others several. The median sepal is posterior in the species without epicalyx, often anterior in those which have an epicalyx.--The petals are twisted either to the right or to the left in accordance with the spiral of the calyx; they are most frequently oblique, as in the other plants with twisted corollas, so that the portion covered in the æstivation is the most developed. The corolla drops off as a whole, united with the staminal tube.--Only the 5 petal-stamens are developed, but they are divided into a number of stamens, placed in 2 rows, and provided only with half-anthers (leaf-segments, see Fig. 446; the sepal-stamens are completely suppressed); these 5 staminal leaves are then united into a tube, frequently 5-dentate at the top, and bearing the anthers on its external side. The pollen-grains are specially large, spherical and spiny. There are from 3 to about 50 carpels united into one gynœceum and placed round the summit of the axis which most frequently projects between them. There is only 1 style, which is generally divided into as many stigma-bearing branches as there are carpels (Figs. 445, 448). The fruit is a schizocarp or capsule. Endosperm (Figs. 447 A, 451) scanty, often mucilaginous round the embryo, which is rich in oil.

The order is the most advanced type of Columniferæ; it stands especially near to the Sterculiaceæ, but is separated from these and from the Tiliaceæ, among other characters, by its 2-locular (ultimately 1-chambered) anthers.

The sub-orders may be arranged as follows:--

I. Carpels in one whorl.

=A.= =The fruit a capsule=, ~most frequently with loculicidal dehiscence, and many seeds in each loculus~.

=1.= GOSSYPIEÆ. The staminal-column is naked at the apex, blunted, or 5-dentate.--Gossypium (the Cotton plant) has an epicalyx of 3 large ovate-cordate leaves, an almost entire, low and compressed calyx. Solitary flowers. Large, most frequently yellow, corollas. A 3–5-valved capsule with many spherical seeds. “Cotton” is the seed-hairs developed upon the entire surface of the seeds (Fig. 447), and consists of long, 1-cellular hairs, filled with air (and therefore white); these are thin-walled, with a large lumen, and during drying twist spirally, and come together more or less in the form of bands. They consist of cellulose, and have a cuticle.--Hibiscus has several, most frequently narrow, epicalyx-leaves, a distinct 5-toothed or 5-partite calyx.--Abutilon; Modiola.

=2.= BOMBACEÆ. The staminal tube is more or less deeply cleft into bundles, sometimes almost to the base; pollen smooth, style simple with capitate, lobed stigma. Almost all plants belonging to this group are trees, and in many instances have large barrel-shaped stems, that is, swollen in the centre, and sometimes covered with large warts. The wood is exceptionally light and soft. The flowers are often enormously large, and have beautiful petals; in some they unfold before the leaves. The capsule-wall is sometimes closely covered on its inner service with long, silky, woolly hairs, while the seeds themselves are generally without hairs. These hairs, however, on account of their brittle nature, cannot be used like those of the Cotton-plant. Digitate leaves are found in the Baobab-tree (Adansonia) from Africa, noted for its enormously thick, but short stem, and in the American Silk-cotton trees (Bombax, Eriodendron, Chorisia). Ochroma, Cheirostemon, Durio, and others also belong to this group. Durio is noted for its delicious fruits, which have a most unpleasant smell.

[Bombax malabaricum is diplostemonous; the five sepal-stamens repeatedly branch, and the filaments bear unilocular anthers; the five petal-stamens bear bilocular anthers.]

=B.= =Schizocarps=, with 1-seeded fruitlets, most frequently nut-like and reniform (Figs. 449, 451).

=3.= MALVEÆ, MALLOW GROUP. The carpels are arranged in one whorl (Fig. 449); the number of stylar-branches equals that of the carpels; fruitlets 1-seeded, reniform, indehiscent, but detaching themselves from one another and from the persistent central column (Figs. 450, 451).--~Malva has an epicalyx of 3 free leaves. ~A flower with 2 suppressed bracteoles is situated in the axil of the foliage-leaves; one of these supports a homodromous foliage-shoot which forms a repetition of the main axis, the other an antidromous flower which continues the branching as a unipared scorpioid cyme.~--Althæa, Rose Mallow, has an epicalyx of 6–9 leaves united at the base.--~Lavatera, Sida, Anoda, Bastardia, etc., have no epicalyx.~

=4.= URENEÆ, have always only 5 carpels arranged in 1 whorl, with 1 ovule in each loculus, and the fruit a schizocarp, generally with nut-like fruitlets provided with warts and hooks; but in some they dehisce by 2 valves (capsule). They differ principally from the other groups in having twice as many stylar-branches as carpels; the staminal tube is naked at the point, blunt or 5 toothed.--The genera Urena, Pavonia, Malachra, Malvaviscus (with berry-like fruits) belong to this group.

II. Carpels arranged in a spherical head in five groups opposite to the petals.

=5.= MALOPEÆ, differ from all the others in having a large number of fruitlets arranged irregularly in a round head, and separating considerably from each other even before maturity; there is, however, only 1 style, divided into a corresponding number of branches (this condition may be considered to have arisen from the branching [dédoublement] of 5 carpels). Malope has 3 large, heart-shaped (Kitaibelia 6–9) epicalyx-leaves, united at the base. Palava has no epicalyx.

POLLINATION. The majority have protandrous flowers, and are pollinated by insects. Between the basal portions of the 5 petals, there are 5 nectaries, protected from the rain by hairs, e.g. in Malva silvestris. When the flower first opens the numerous anthers occupy the centre of the flower, and the still undeveloped stigmas are concealed in the staminal tube; in the next stage the anthers are withered and empty, and the stigmas protrude and assume their places (Fig. 452). The large-flowered forms, it appears, are pollinated only by insects; but self-pollination takes place in small-flowered forms, as, for example, in Malva rotundifolia, in which the stylar-branches, twisting themselves, place the stigmas in between the undeveloped anthers.

DISTRIBUTION. 800 species (63 genera), most of which are natives of the Tropics, especially America. Althæa and some of the species of Malva are natives of the temperate regions of the Old World, the latter is also found in North America. Gossypium is tropical, no doubt especially Asiatic (G. herbaceum from India; G. arboreum from Upper Egypt). Cotton was introduced into Greece in the time of Herodotus, and was cultivated in America before the arrival of the Europeans.

USES. Pungent and poisonous properties are entirely wanting; mucilage, on the other hand, is found in abundance in all parts of the plant. Medicinal: the root of Althæa officinalis, leaves and flowers of Malva-species (M. silvestris vulgaris and borealis) and Gossypium.--The seeds contain a large quantity of fatty oil, which is in some cases extracted (Cotton-seeds and others). The seed-hairs of the Cotton plant are the most important product of the order. The cultivated forms of Cotton belong to several species: G. barbadense, herbaceum, religiosum, arboreum (Nankin), hirsutum, and others. According to other botanists, there are only 3 species. Bast is obtained from e.g. Hibiscus cannabinus (Gambo-hemp, Africa), Paritium tiliaceum and Sida retusa. The fruits of certain species of Hibiscus (e.g. H. esculentus, from Tropical Africa) are used in tropical countries as a vegetable before they are ripe.--The colouring matter in the flowers of Althæa rosea, var. nigra, is used for colouring wines, and hence is extensively cultivated in certain parts of Europe.--Ethereal oils and sweet-scented flowers are rare; but several species possess a peculiar musk-like odour (Malva moschata, Hibiscus abelmoschus, and others).--Many are cultivated as ornamental plants on account of the large flowers, e.g. Hollyhock (A. rosea, etc.), Lavatera trimestris, Malope grandiflora and trifida, Malva-species, Hibiscus rosa sinensis, syriaca; Sphæralcea, etc.

Family 14. =Tricoccæ.=

The very large order Euphorbiaceæ and three smaller ones belong to this family. They have in common: unisexual, hypogynous, frequently regular flowers, the perianth most frequently single, rarely double, or entirely wanting; there is such a great variety in the structure and parts of the flower that one only can be cited as the rule: viz. the simple gynœceum composed of 3 carpels forming a 3-locular ovary, which is frequently more or less deeply grooved (hence the name, Tricoccæ); in the inner angles of the loculi are found 1 or 2 (never several) pendulous (except Empetraceæ), anatropous ovules, with upward and outwardly turned, frequently swollen, micropyle (Fig. 455). The seed most frequently has a large endosperm and a straight embryo (Figs. 455 B, 464).--~The family approaches the nearest to the Gruinales and Columniferæ; it may perhaps be regarded as an offshoot from the Sterculiaceæ.~

Order 1. =Euphorbiaceæ.= Flowers unisexual. In each of the loculi of the ovary, generally 3, there are 1 or 2 pendulous ovules with upward and outwardly turned micropyle. The placenta protrudes above the ovules (Figs. 454, 461 B). On the ripening of the capsule the 3 carpels separate septicidally, frequently with great violence, ejecting the seeds and leaving a central column. Endosperm copious.--For the rest, the flowers present all stages, from genera with calyx and corolla, to those which are the most reduced in Nature, namely the naked, 1-stamened flowers of Euphorbia.

The same variety which is found in the flower is also present in the vegetative parts. Some are herbs, as our Spurges, others are shrubs and trees; some African Euphorbia-species even resemble the habit of a Cactus. Leaf-like branches with rudimentary leaves are found in Phyllanthus (sub-genus Xylophylla) (Fig. 456). The leaves are scattered or opposite, often stipulate; they are nearly always simple. Large, highly-branched cells containing a great quantity of pungent latex are found in many, and watery juice in others. Glands and glandular hairs are general.--Only a few genera can be considered in this book.

As an example of the most perfect flowers (which partly reproduce the Geraniaceous type) may be mentioned, Croton, Manihot, and Jatropha; 5 sepals, 5 petals, sometimes gamopetalous, andrœcium diplostemonous, or many-stamened, often monodelphous.

Ricinus (Castor-oil) (Figs. 453–455); monœcious; the ♂-flowers, situated in the lower portion of the inflorescence, have 5 perianth-leaves and a large number of branched stamens; the ♀-flower has 3–5 perianth-leaves; 3 bifid styles. Leaves peltate, palmately lobed. The seeds (Fig. 455) contain an abundance of fatty oil and large aleurone grains.--Mercurialis (Mercury): the perianth is most frequently 3-merous; in the ♂-flowers 9–12 stamens; in the ♀-flowers most frequently a 2-locular gynœceum.--Phyllanthus: Pr3 + 3, A3, united in some and forming a column in the centre of the flower (Figs. 457, 458); Xylophylla is a section of this genus.-- Hura crepitans (Sand-box tree) has a many-carpellate gynœceum, which separates with great violence when ripe.--A drupe is found in Hippomane mancinella (the Mancinil-tree, W. Ind.)--Alchornea (Coelebogyne) ilicifolia is well known on account of its “parthenogenesis”; only the ♀-plant has been introduced into Europe, but it nevertheless produces seeds capable of germination; these have generally several embryos.

Euphorbia (Spurge) has the most reduced flowers, which are borne in a very complicated inflorescence. Each ♂-flower (Fig. 460 B) is naked, and consists of one stamen only (terminal on the axis). In the closely allied genus Anthostema, a small perianth is situated at the place where, in Euphorbia, there is a joint in the “filament,” (Fig. 461 A). The ♀-flowers (Fig. 460) are naked, with a 3-locular ovary and 3 bifid styles. (Anthostema has a distinct perianth (Fig. 461 B); in a few Euphorbias traces of a perianth are present). In Euphorbia the ♂-and ♀-flowers are grouped into flower-like inflorescences termed “cyathia.” Each cyathium consists of a centrally placed ♀-flower which is first developed, surrounded by 5 groups of ♂-flowers (stamens) placed in a zig-zag, with a centrifugal order of development (Figs. 459, 460 B), that is, in unipared scorpioid cymes; these flowers are surrounded by an involucre of 5 leaves united into a bell-shaped structure (Fig. 459, 1–5) (resembling a calyx); on its edge are placed 4, generally crescent-like, yellow glands, one in each of the intervals, except one, between the lobes of the involucre (shaded in Fig. 459; see also Fig. 460 A). Scale-like thin structures (floral-leaves?) are situated between the ♂-flowers. The ♀-flower has a long stalk, and finally bends down on one side, namely to the place on the edge of the involucre where the gland is not developed. These cyathia are again arranged in an inflorescence which commences as a 3–5-rayed umbellate cyme (pleiochasium), the branches of which ramify dichasially and finally as scorpioid cymes.--Latex, with peculiar-shaped starch-grains, is found in laticiferous cells (especially in the Cactus-like, leafless species.)

205 genera; more than 3,000 species; especially in the Tropics.--Many are used on account of the oil, and of the pungent (aperient, poisonous, anthelmintic, etc.) properties in the latex or the seeds. OFFICINAL: “Cascarilla-bark” of Croton eluteria; the fatty oil of the seeds of Croton tiglium (Trop. Asia); “Castor oil” from Ricinus communis (Africa, and cultivated in all warm climates throughout the world); the glandular hairs of Mallotus philippinensis (“Kamala”); this also yields a red dye. Gum “Euphorbium” is the hardened (resinous) latex of the Cactus-like Euphorbia resinifera (Morocco).--NUTRITIVE plants: Manihot utilissima and other species (Maniok, Am.). Their large, farinaceous roots form a very important article of food in the Tropics (Cassava-flour, Tapioca or Brazilian arrowroot). The fresh latex of the root in some species is a powerful poison; but the poisonous properties are diminished by roasting or cooking. Caoutchouc is obtained from Siphonia elastica (Trop. S. Am.). The vegetable tallow of the Chinese tallow-tree (Stillingia sebifera) is used in large quantities in soap factories. An indigo-like dye is obtained from Crozophora tinctoria, and is also found in Mercurialis perennis. Shellac is obtained from Aleurites laccifera. ORNAMENTAL plants: Acalypha, Croton, Dalechampia.--Hippomane is poisonous.

Order 2. =Buxaceæ.= This order differs from the Euphorbiaceæ in having the micropyle turned inwards; the ♂-flower has a 4-partite perianth and 4 stamens; the ♀-flower a 6-partite perianth and 3 carpels. Capsule with loculicidal dehiscence, the inner layer being detached elastically from the outer.--30 species. Shrubs without latex and with evergreen leaves.--Buxus sempervirens (Box) is an ornamental shrub (poisonous); it has a very hard and valuable wood which is used for wood-engraving and carving.

Order 3. =Callitrichaceæ.= Aquatic plants, growing at the bottom of shallow water, with opposite, simple, undivided, entire, exstipulate leaves, which are generally crowded and form a rosette in the apex of the branches. The flowers are unisexual (monœcious) and borne singly in the leaf-axils; they have no perianth, but are provided with two delicate bracteoles; the ♂-flowers consist of only 1 terminal stamen (Fig. 462); the ♀-flowers of a bicarpellate gynœceum (Fig. 463) which is originally 2-locular, but later on becomes 4-locular, as in the case of the gynœceum of the Labiatæ, by the formation of a false partition-wall; in each loculus there is 1 pendulous ovule with the micropyle turned outwards. Fruit a 4-partite schizocarp (Fig. 464). 25 species.--Callitriche.

Order 4 (?). =Empetraceæ.= 4 species. Empetrum; E. nigrum (Crowberry) is a heather-like, moorland, evergreen undershrub with linear leaves, having a deep groove closed with hairs, on the under side. The erect ovules show the greatest deviation from the Euphorbiaceæ. Diœcious (and ☿); S3, P3; in the ♂-flower, 3 stamens; in the ♀-flower, a 6–9-locular ovary. Fruit a drupe.

Family 15. =Terebinthinæ.=

The diagram of the flower (Figs. 465–467) is the same as in the Gruinales, namely S, P, A2 and G in whorls of 5 (less frequently 3, 4, 6, 8), and the same modifications also occur with the suppression of the petal-stamens, etc. But a ring or sometimes cup-like glandular structure (disc) is found between the andrœcium and the gynœceum (Figs. 465, 466). The flowers similarly are regular, hypogynous, ☿ and polypetalous, though exceptions are found to all these characters: thus, for example, united sepals and petals frequently occur, and, in some orders, unisexual flowers by the suppression of one sex. In most cases the flowers are small, greenish-yellow, and arranged in paniculate inflorescences. The carpels (most frequently 5) are free in a few, but generally united into a multilocular gynœceum; rarely more than 1 or 2 ovules in each loculus. The gynœceum in the Anacardiaceæ is so reduced that it has only 1 fertile loculus with 1 ovule.--The ovules are epitropous, i.e. anatropous with outward-turned raphe (except the Anacardiaceæ).--The majority of the species are trees and shrubs with scattered, often compound (pinnate) leaves without stipules, and as in addition they frequently contain aromatic, especially turpentine-like substances, they assume a certain resemblance to the Walnut trees, and were formerly classed with them mainly on this account. In a series of genera the volatile, scented oils are found in special glands in the bark of the branches and in the leaves, in the latter case appearing as pellucid dots. This family includes several orders which are somewhat difficult to distinguish from each other.

Order 1. =Connaraceæ.= This order forms the connecting link between Terebinthinæ and Rosifloræ (Spiræa) as well as Leguminosæ, with which they are sometimes classed. The flowers have 5 5-merous whorls; 2 ovules in each loculus; micropyle turned upwards. Fruit a follicle, rarely a collection of follicles. Seed with aril. Shrubs with scattered (most frequently pinnate) leaves, without stipules. 170 species. Tropical.

Order 2. =Meliaceæ.= Trees and shrubs with scattered, often pinnate leaves without pellucid dots and exstipulate; the leaflets are nearly always entire. Flowers small in paniculate inflorescences. Calyx and corolla 4–5-merous; 2 whorls of stamens; 3–5 carpels in the gynœceum. A very characteristic feature is the union of the filaments into a tube, on the edge of which stipule-like teeth are often found. There are most frequently 2 ovules in the loculi; fruit a capsule with many winged seeds in Swietenia (Mahogany tree; Trop. Am.), Cedrela, etc.; berries in others. The wood of Cedrela is used for making cigar boxes. 550 species; tropical.

Order 3. =Rutaceæ.= Leaves glandular with pellucid dots. The type is the same as that of the family. Flowers 4–5-merous. The ovary is most frequently 4–5-grooved. Disc well pronounced, often appearing as a “gynophore.” The majority are shrubs with alternate or opposite, compound, more rarely simple, leaves.

=A.= The ovary is deeply 2–5-cleft with basal styles which are more or less united; the carpels in some genera are entirely free (groups 1, 2). The fruit is capsular and most frequently dehisces like follicles along the ventral suture or septicidally, so that a horn-like internal layer (endocarp) separates elastically from the external layer.

=1.= ZANTHOXYLEÆ. Zanthoxylum; Choisya; Evodia.

=2.= BORONIEÆ. Australia.--Correa.

=3.= DIOSMEÆ. Heather-like shrubs; Africa.--Diosma, Coleonema, Empleurum and Barosma. OFFICINAL: Barosma crenulata and betulina, “broad Buchu leaves” (B. serratifolia and Empleurum serrulatum, “narrow Buchu-leaves”).

=4.= RUTEÆ. Ruta (Figs. 465–467) graveolens is an herbaceous, glaucous, strongly smelling plant with bipinnate leaves and yellow flowers; the terminal flower is 5-merous, the others 4-merous (S. Eur.).--Dictamnus; zygomorphic flower. ~The individual carpels of the fruit separate from each other, and dehisce like follicles, upon which the internal layer is detached elastically and springs out, carrying the seeds with it. Several species are ornamental plants.~

=5.= CUSPARIEÆ. American. Flowers often zygomorphic with gamopetalous corolla; stamens 5.--Ticorea; Galipea (G. officinalis; S. Am.; “Cortex angosturæ”); Cusparia; Almeidea.

=B.= The ovary is entire or only slightly grooved; the style is terminal, undivided. The fruit is most frequently a drupe or berry.

=6.= TODDALIEÆ. Ptelea; winged fruit. The buds are enclosed in the leaf-sheath. Skimmia; Phellodendron.

=7.= AURANTIEÆ, ORANGE GROUP. Fruit a berry with a leathery external layer.--The most typical flower is found for example in Limonia: S5, P5, A5 + 5, G5 (2–5).--Citrus has 4–5–8-merous flowers, a gamosepalous, dentate calyx, free petals, one whorl of stamens which are split irregularly into several bundles (Fig. 470). The fruit is a multilocular berry provided with a thick, tough, outer layer. The juicy pulp, which fills up the loculi and envelopes the seeds, is formed from many large-celled, juicy hair-structures which arise on the inner side of the walls of the loculi and by degrees entirely fill them up; the dissepiments remain thin, and form the partitions so easily separating from each other (Fig. 469). The seeds in many instances are remarkable for containing several embryos. The blade of the leaf is separated from the frequently winged stalk by a node (and hence is a compound leaf with only the terminal leaflet developed?) (Fig. 468); in other genera, as Triphasia, there is a fully developed trifoliate leaf. Thorns are frequently developed.--~The species of this genus, which is a native of the warmer parts of S. E. Asia, are very hard to separate. The differences are found in the forms of the fruit, the leaves and the leaf-stalks, and in the number of stamens. Citrus medica, “Cedrat” (Ind.); C. limonum, “Citron,” “Lemon” (introduced into Italy in the 3rd to 4th century). OFFICINAL: the fruits and essential oil of Lemon. C. aurantium from E. Asia, the Orange (introduced into Italy in the 14th century). C. vulgaris (Fig. 468), Bitter Orange (introduced into Europe at the time of the Crusades); the unripe Bitter Oranges, and peel of the Bitter Orange is officinal; it is from the flowers of this species especially that the essence of Neroli is made. C. limetta, C. bergamia, Bergamot; essence of Bergamot is officinal. C. decumana, Pomalo, a native of the Islands of the Pacific. About 780 species; chiefly tropical.~

Order 4. =Burseraceæ.= Fruit a drupe; 1–5 stones. The bark, as well as the other parts, contain strong aromatic resins and balsams, and hence several species are used: the Myrrh tree, Commiphora (Balsamodendron) from Arabia and Africa; OFFICINAL: Myrrha (Commiphora myrrha). Mecca-balsam from C. opobalsamum, Arabia; E. Africa. The Incense-tree (Boswellia) from the same parts of the globe and E. India. The incense of B. carteri is medicinal (Frankincense). The resin (Elemi) of Protium-species is officinal, and is used technically for varnish (S. Am.). Takamahaka-resin from Elaphrium (S. Am.) Protium (Icica); Amyris (1 carpel). 270 species; tropical.

Order 5. =Zygophyllaceæ.= The majority have opposite, pinnate leaves with stipules. Leaves without pellucid dots. The filaments have a scale on the inner side. The most important is Guaiacum officinale (West India), the wood (Lignum Vitæ) of which is very hard and heavy, this wood and Gum-guaiacum are officinal. Others have a peculiar repulsive smell and taste: the Creosote shrub (Larrea mexicana) and Zygophyllum simplex. Tribulus terrester is a common weed in S. Europe. Fagonia. Peganum harmala (South of Russia) yields a red dye.--110 species; especially in the Tropics; several species in sandy deserts. Nitraria.

Order 6. =Simarubaceæ.= This order is distinguished by the abundance of bitter substances which it contains (Quassine) especially in the bark and the wood. The wood of Quassia amara (Guiana, Antilles) is officinal; Picraena excelsa yields Jamaica Quassia; the bark of Simaruba, Simaba-species and others is used. Ailanthus glandulosa is a garden plant (pinnate leaves, winged fruit).--110 species. Tropical.

Order 7. =Ochnaceæ.= Flowers diplostemonous, 5-merous. The unilocular ovaries, which are individually free, project considerably into the air around the gynobasic style; 1 ovule in each loculus; the fruitlets are drupes. Shrubs; leaves alternate, with stipules. Ochna; Ouratea.--160 species; tropical; especially American.

Order 8. =Anacardiaceæ.= The ovary rarely contains more than 1 ovule, even though there be several loculi and several carpels; in Anacardium all the 10 stamens except one become suppressed. Resin passages.--Anacardium. The most peculiar feature is the development of the flower-stalk into a fleshy body about the form and size of a pear (A. occidentale from Trop. Am. and A. orientale from E. Ind.) which bears the kidney-shaped nut (the so-called “Cashew-nut”) on its apex. Mangifera indica (the Mango-tree, from E. Ind.) is cultivated in several tropical countries on account of its delicious drupe. Similarly, species of Spondias (S. dulcis, Pacific Islands, S. lutea). Several species of Rhus are ornamental shrubs in this country, for instance, R. typhina (N. Am.), R. cotinus (the Wig-tree, the barren flower-stalks of the panicles being feather-like and hairy); R. toxicodendron (Poisonous Sumach, from N. Am.) is poisonous. Chinese galls are produced by the sting of a leaf-louse (Aphis chinensis) on R. semialata (China), and Japanese wax is from the seeds of R. succedanea (Japan). Considerable quantities of Sumach (R. coriaria) are used in tanning and as a black dye. OFFICINAL: the mastic resin of Pistacia lentiscus (the Mastic-tree, from the Mediterranean). The fruits of Pistacia vera (Syria) are edible; P. terebinthus and others yield turpentine.--450 species; tropical.

Order 9. =Icacinaceæ.= Flowers 4–5-merous; haplostemonous; receptacle convex or cup-like surrounding the gynœceum; in the (single) loculus of the ovary, 2 anatropous, pendulous ovules.--200 species; tropical.

Family 16. =Aesculinæ.=

The essential characters of this family are in the main the same as those of the Terebinthinæ and Gruinales. The flowers are hypogynous, perfect, with free petals, 5-merous (S5, P5, typically A5 + 5, all of which, however, are not generally developed; in our native orders there are only 7–8 stamens), and most frequently a 3-merous, 3-locular gynœceum (less frequently 2 or 5 carpels with as many loculi). In each loculus there are usually only 1–2 ovules. A deviation from the preceding families is the frequent zygomorphy of the flower, with, as a rule an oblique plane of symmetry (Fig. 471). When a disc is developed it is placed outside the stamens. The majority have no endosperm (Fig. 473).--The members of the family are nearly all trees.

The family is closely allied to the Terebinthinæ, but unlike this it never has aromatic properties, and differs also in the position of the nectary, in the flowers, which are often irregular with a reduction in the number of stamens, and in the ovule which is usually ascending with micropyle pointing downwards (the Terebinthinæ having the micropyle turned upwards), etc. It is also related to Frangulinæ, the Staphyleaceæ being the chief connecting link; but the Æsculinæ generally have compound leaves.

Order 1. =Staphyleaceæ.= Leaves opposite, often compound. Flowers regular, ☿, 5-merous in calyx and corolla, 5-stamened. The stamens are placed outside the nectary. Ovary syncarpous or 2–3-partite with free styles. The capsule is thin, bladder-like, 2–3-locular, opening at the apex, and has several very hard seeds with a shining testa without aril. Endosperm. Staphylea pinnata (S. Europe) and trifoliata (N. Am.) are cultivated in gardens; they have white flowers in pendulous, axillary racemes or panicles.--16 species.--Staphylea is found in the Tertiary of N. America.

Order 2. =Melianthaceæ.= Glaucous shrubs with scattered, pinnate leaves, and large stipules. Melianthus.--8 species; S. Africa.

Order 3. =Sapindaceæ.= Trees or shrubs, often climbing by tendrils (lianes with anomalous structure of the stem) and with compound leaves. The flowers, in most cases, are small, insignificant, and without scent, and in some polygamous and zygomorphic. S4–5, P4–5, A8 (less frequently 5–10) inside the nectary (disc); ovary generally 3-locular, with 1–2 ovules in each loculus (raphe ventral, micropyle turned downwards). Seed without endosperm, often with an aril. The embryo is often thick and curved (Fig. 473).

Æsculus (Horse-Chestnut). Trees with opposite, digitate, dentate leaves without stipules; the inflorescence is composed of unipared scorpioid cymes arranged in a pyramidal panicle (termed a thyrsus). The flowers are irregular, with an oblique plane of symmetry (through the 4th sepal, Fig. 471); there are 5 sepals, 5 free petals, of which the one lying between S^3 and S^5 is the smallest (see Fig. 471) and may be absent; stamens 7 (5 + 2), three being suppressed; gynœceum simple, 3-carpellary and 3-locular, with single style; of the two ovules one is ascending, the other descending (Fig. 472).--The fruit is a 3-valvate, sometimes spiny, capsule, with loculicidal dehiscence, the seed having a large hilum, a curved embryo without endosperm and united cotyledons (the radicle lies in a fold of the testa, Fig. 473). Æ. hippocastanum (Greece, Asia), introduced into cultivation about 300 years ago; the majority of the other species, e.g. Æ. pavia, etc., several of which are frequently cultivated in gardens, are from N. America. ~The flower of the Horse-Chestnut is adapted for bees, whose abdomen touches the anthers or style when visiting the flower. The flowers are protogynous.~

The other Sapindaceæ have most frequently 4 sepals, 8 stamens, various fruits (septicidal capsule, nuts with or without wings, schizocarp), etc. Serjania, Cardiospermum, Sapindus, Koelreuteria, etc. (about 118 genera, 970 species). The seeds of Paullinia sorbilis contain caffeine, and are used as “Pasta guaranà,” in the North Western Brazils in the manufacture of a common drink. Nephelium (or Euphoria) litchi (with edible aril), and other species, from Asia.

Order 4. =Aceraceæ.= This order is so closely allied to the Sapindaceæ, that some authorities have classed it with them. The main difference is in the regularity of the flowers, and the =2=-merous gynœceum (in abnormal cases several carpels occur).--They are trees, and, like the Horse-Chestnuts, have opposite leaves without stipules; in Acer the leaves are palminerved, but imparipinnate in Negundo, a plant frequently cultivated in gardens. The flowers are often unisexual, polygamous (some species have ☿-, ♂-and ♀-flowers); sepals 5, petals 5 free, =stamens 8= (that is, 5 + 5, but the two median ones are absent) inside a large disc. Fruit a samara (schizocarp) with 2 winged, nut-like fruitlets (Fig. 474). In each of the 2 loculi of the ovary are 2 ovules. Embryo curved, with thin, folded cotyledons. Endosperm absent.--~The inflorescences are racemes with a more or less elongated main axis and terminal flower (which sometimes has 10 stamens); when the lateral branches are developed they are similar to the main axis. In some species both corolla and petal-stamens are suppressed. Acer is pollinated by insects, Negundo by the wind.--88 species; North Temperate zone. Acer in the Tertiary from the Oligocene. The following are native plants: Maple (Acer campestre), Sycamore (A. pseudoplatanus, doubtful native). Important as avenue trees and timber. Sugar is obtained from the spring sap of the Sugar Maple (N. Am.).~

Order 5. =Malpighiaceæ.= A tropical (especially American) order closely related to the Aceraceæ, having often the same form of fruit (but 3-partite). Some species are lianes with anomalous stem-structure. Leaves opposite. The flowers are regular or obliquely zygomorphic (the plane of symmetry passing through sepal 3), with S5, P5, A5 + 5, G3; 1 pendulous ovule in each loculus. Important characteristics for identification are the numerous grandular structures on the sepals. Peculiar 2-spined hairs are found in some. Malpighia, Bunchosia, Galphimia, Tetrapterys, Heteropterys, etc.--About 600 species.

Order 6. =Erythroxylaceæ.= Sepals 5, petals 5 (with a ligular corona), 10 stamens in one bundle. Gynœceum 3-locular. Fruit a drupe. Tropical (especially American) trees and shrubs, the Coca-plant (Erythroxylon coca) being best known. Its leaves are considered by the inhabitants of Chile and Peru to be one of the indispensable necessaries of life; they are chewed, and possess intoxicating, exhilarating properties, and contain the alkaloid cocaine, which is frequently employed as a local anæsthetic.--103 species; chiefly in America.

Order 7. =Vochysiaceæ.= Trees; Trop. Am. 1 stamen.--140 species.

Order 8. =Trigoniaceæ.= Shrubs; Trop. Am.--30 species.

Order 9. =Tremandraceæ.= Polygalaceæ with regular flowers.--27 species. Australia.

Order 10. =Polygalaceæ.= Herbs or shrubs (some tropical species are lianes) with scattered (rarely opposite), simple and most frequently quite entire leaves, without stipules. The flowers are usually borne in terminal spikes or racemes, and are strongly zygomorphic (the plane of symmetry being median); they have 5 free sepals, the 2 lateral ones of which (4 and 5 in Figs. 475, 476) are very large, petaloid, and frequently project on each side like the “wings” of a Pea-flower; petals 5, of which the two lateral ones are wanting or rudimentary (dotted on Fig. 475), and the anterior “the keel” (Fig. 476 c) is large, hollow and boat-shaped, and frequently with a lobed or fimbriated edge (Fig. 476 A and B, c); stamens 8, the two median ones being absent, all united into a tube split along the back, which is also slightly united to the keel (the anthers, often 2 locular, open by pores, Fig. 476 B, st); the 2 median carpels form a bilocular ovary. 1 pendulous ovule in each loculus (Figs. 476 C, 475); capsule compressed with loculicidal dehiscence, rarely a nut. Polygala (Milk-wort).

470 species; distributed over the whole globe (none Arctic). OFFICINAL: the root of P. senega, from N. Am. Some are used as ornamental plants.

POLLINATION. The flowers of Polygala are pollinated by insects (chiefly bees). The fimbriated processes of the anterior petal support the insect when it alights. The anthers lie on each side of the stigma in the pouch of the anterior petal; the apex of the style is spoon-shaped, and immediately behind it is a viscid stigmatic lobe. In reaching the honey the proboscis of the insect must come in contact with the pollen and the viscid stigma, by which it is rendered sticky; this ensures the pollen adhering to the proboscis and so being carried to other flowers.

Family 17. =Frangulinæ.=

The plants belonging to this family, with very few exceptions, are trees or shrubs. The leaves are usually simple; stipules may be absent or present. The flowers in almost all the orders are small, green or whitish; they are always regular, 4-or 5-merous with 2–5 carpels, but never have more than 1 whorl of stamens, which in Rhamnaceæ and Ampelidaceæ are placed opposite the petals (typically 5 + 5 or 4 + 4 stamens, of which however either the external or internal whorl is always wanting); hypogynous or slightly perigynous, in Rhamnaceæ only strongly perigynous or epigynous; generally ☿; the calyx is inconspicuous; petals free or slightly united. Gynœceum simple; ovary generally multilocular; style short or entirely wanting. A disc is nearly always developed in the flower, but is found sometimes inside the staminal whorl, sometimes outside it or between the stamens. The ovules are apotropous (anatropous with dorsal or ventral raphe).

Order 1. =Celastraceæ.= Euonymus europæa (Spindle-tree) may be chosen as a type. It is a shrub with simple, opposite leaves and small caducous stipules. The small, greenish-yellow flowers, borne in regularly-branched dichasia, are regular, ☿, with 4 whorls, 4-(or 5-) merous in regular alternation. There is a thick disc upon which the polypetalous corolla (imbricate in the bud) and the stamens are borne, with a slightly perigynous insertion. The style is short and thick; the ovary has 2 erect ovules in each loculus. The fruit is a red, 4-valvate capsule with loculicidal dehiscence; the seeds are few in number, and have a large, red-yellow aril (developed from the micropyle). Embryo green, in a large, fleshy, white endosperm. ~The dingy yellow flowers are generally visited only by flies and ants for the sake of the honey secreted by the disc, and while they run about on the flowers they touch the anthers and stigmas, now with one part of the body, now with another. The flower is protandrous. The stigmas are not developed till several days after the opening of the anthers.--Celastrus, Cassine, Catha, etc.~

38 genera; 300 species. Distributed over the entire globe, with the exception of the colder districts, and especially in the Tropics. Some are ornamental bushes (Euonymus japonica). The leaves of Catha edulis are used by the Arabs and Abyssinians in the same way as those of Coca by the Peruvians.

Order 2. =Hippocrateaceæ.= 150 species; tropical; chiefly lianes. S5, P5, A3, G3. Anthers extrorse.

Order 3. =Aquifoliaceæ (Hollies).= The genus Ilex forms almost the entire order. (175 species out of 180; especially from S. Am.) They are shrubs or trees with scattered, leathery, simple leaves (in Ilex aquifolium, spiny) with very small stipules. The flowers are small, white, and borne in few-flowered inflorescences in the axils of the foliage-leaves; they are most frequently unisexual and diœcious. There are 4–5 sepals, petals, stamens and carpels in regular alternation; the calyx and corolla have their leaves slightly connate; stamens slightly adnate to the corolla; the ovary is generally almost spherical with a thick, sessile stigma (Fig. 477). This order deviates especially from Celastraceæ in the absence of the disc and in having only 1 (pendulous) ovule in each of the 4 loculi of the ovary, and in having a drupe with generally 4 stones. Embryo extremely small, at the apex of the large endosperm, with the radicle directed upwards.--~3 genera.--I. aquifolium (Holly) principally on the coasts of European countries; from Norway to W. Denmark, and further westward. It is a common garden shrub with stiff, shining leaves and red fruits. Several South American species contain so much caffeine that they may be used as a beverage in the place of tea (I. paraguayensis, Paraguay tea, or Maté). The Holly does not contain caffeine.~

Order 4. =Ampelidaceæ (Vines).= Shrubs with the stem swollen at the insertion of the petioles and climbing by tendrils borne opposite the leaves (Figs. 478, 479). The leaves are scattered (generally 1/2), stalked, stipulate, frequently palminerved and lobed, divided or compound. The small, greenish flowers are generally borne in paniculate inflorescences, whose position is the same as that of the tendrils (Fig. 478); they are hypogynous or slightly perigynous, ☿, with 4–5 sepals, petals, stamens (which, as in the Rhamneæ, are opposite the petals; Fig. 480 A, B) and 2 carpels. The calyx is very small, entire, or slightly dentate; corolla valvate, and in some falling off as a hood, since the individual parts remain united at the summit (Fig. 480 A). Between the stamens and gynœceum is situated an hypogynous disc, with 5 lobes alternating with the stamens (Fig. 480 A, B, E). In each loculus of the 2-locular ovary there are 2 erect ovules (E); the style is short or wanting. The fruit is a berry. The embryo is small and lies in a horny, sometimes slightly folded (ruminate) endosperm (Fig. 480 C, D).

Vitis and Ampelopsis (5-merous flowers); Cissus (4-merous flower); Leea (without stipules, corolla gamopetalous). The inflorescence in Pterisanthes (E. Ind.) has a peculiar, flat, leaf-like axis, on the edges of which ♂-flowers are borne, and on the surface ♀-flowers.

The TENDRILS in Ampelidaceæ are modified branches, since they bear leaves and may be abnormally developed as branches with foliage-leaves, and finally the inflorescences are borne in the position of the tendrils, and tendrils are met with which are partly inflorescences. The explanation of the position of the tendril, namely, right opposite the foliage-leaf but without a subtending-leaf, has been much disputed. The relative positions are as follows: in Vitis vinifera the following two kinds of shoots and relative positions are found (the other species deviate in one or other particular), (a) LONG-BRANCHES, which have 2 scale-leaves and a large number of foliage-leaves with a divergence of 1/2; opposite the lowest 3–5 foliage-leaves no tendrils are found, then follow: 2 foliage-leaves with tendrils, 1 without a tendril, 2 with and 1 without, etc., with great regularity. Buds are developed in the axils of the foliage-leaves (Fig. 479): these develop into (b) DWARF-BRANCHES, which commence with 1 laterally-placed scale-leaf (fore-leaf; Fig. 481 v) succeeded by several foliage-leaves with a divergence of 1/2 (in a plane at right angles to that of the mother-shoot), but the whole shoot is extremely small, and often dries up and drops off in the autumn, so that only the scale-leaf, v, with the bud (Fig. 481 lt{1}_) in its axil remains. This bud in the following year developes into a new long-branch, and since its leaves lie in a plane at right angles to that of the dwarf-branch, their plane coincides with that of the long-branch from which it is developed (the grandmother axis).--The tendrils no doubt may most correctly be regarded as the modified main axis which has been pushed aside by a lateral branch. The branches are then sympodia, whose successive shoots bear alternately 1 and 2 foliage-leaves: thus, on the figure there are portions altogether of 5 shoots (I.-V.), the 1-leaved ones are shaded, the 2-leaved ones are white. The following facts however are adverse to this theory: (1) the first leaf on an axillary bud is then situated 180° from the subtending leaf (e.g. the lowermost shaded leaf, Fig. 479, 180° from the lowermost white leaf), whilst the rule in the Dicotyledons is that it is placed only about 90° to one side. (2) The buds (Fig. 479 K) from which the dwarf-branches develop, must then be accessory and sister-buds to the sympodial shoots, but their first leaves have a different relative position to this, which is very peculiar, and a still more remarkable fact is that the buds, K, etc. are similar in structure and present in all the axils; thus we only find accessory buds in the cases where no tendrils are opposite to the leaves, and the main bud must then be considered to be suppressed. (3) The development proves that the tendrils arise on the side of a vigorous growing-point of the stem or by its division, and do not develop, as might be expected, from the apex of the shoot. But these relations however, find their analogues and are all capable of explanation, whereas other less natural modes of explanation are opposed to them.

435 species; especially in the Tropics; they are rarer in America. In N. Am. some Vitis-species and Ampelopsis quinquefolia are found. Vitis vinifera is supposed to have originated in the districts East and South of the Caspian Sea. Wine is obtained from Vitis-species, especially V. vinifera, and “raisins,”--(the name “currants,” given to a special variety with small, seedless fruits, is derived from Corinth).--The species of Ampelopsis (Virginian Creeper) are cultivated as ornamental plants.

Order 5. =Rhamnaceæ.= The stamens are placed opposite the petals as in the Ampelidaceæ (Fig. 482), but the flowers are much more perigynous or entirely epigynous. The trees and shrubs belonging to this order have simple, most frequently penninerved leaves with stipules; frequently thorny (modified branches). The flowers are inconspicuous, sometimes unisexual (Fig. 482), and have 5 (-4) sepals, petals, stamens, and generally 3 (2–5) carpels. The calyx has valvate æstivation. The petals are very small (generally less than the sepals), often spoon-like, hollow, and embracing the stamens; a disc covers the inner surface of the thalamus or the base of the style in the epigynous flower; gynœceum simple, with one style and one erect ovule in each loculus. The fruit is most frequently a drupe. The embryo is large, often green or yellow, with endosperm.

Rhamnus (Buckthorn) has a juicy drupe with 3 (2–4) stones, surrounded at the base by the persistent portion of the receptacle; the disc is thin. R. cathartica (common Buckthorn): diœcious, with opposite, serrate leaves. R. frangula (Alder Buckthorn): flowers ☿, with scattered, entire leaves.--~Ceanothus (N. Am., with richly-flowered inflorescences and a fruit closely resembling that of the Euphorbias). Phylica, Pomaderris (Austr., fruit a capsule). Zizyphus, Paliurus, Colletia (S. Am.) are thorny shrubs; C. spinosa has thorny shoots with small, caducous leaves; the seedling has normal foliage-leaves. Others climb by tendrils as in the Ampelidaceæ, e.g. Gouania.~

475 species, 40 genera; chiefly in temperate and tropical climes. Some are medicinal plants, the bark and fruit having purgative properties (the bark of Rhamnus frangula and “Cascara Sagrada” from the bark of R. purshiana are officinal). The fruits and seeds of others are edible, for example, the fruits of Zizyphus lotus, Z. vulgaris, Z. spina Christi, etc. Green and yellow dyes are obtained from the fruit of R. cathartica, infectoria and others (Avignon grain). Ceanothus-, Rhamnus- and evergreen Phylica-species are ornamental shrubs.

Family 18. =Thymelæinæ.=

Exclusively trees or shrubs with simple, entire, scattered leaves without stipules. They have a strongly perigynous, regular, 4-merous flower. The receptacle (often coloured) envelopes a simple gynœceum formed of =1= carpel and with, in most cases, =1= ovule, bearing on its edge 4 (or 5) petaloid sepals and, but rarely at the same time, small, scale-like petals. The corolla is most frequently entirely wanting (and hence these plants were formerly reckoned among the Monochlamydeæ); frequently only one of the 2 whorls of stamens, which are situated on the inner side of the edge of the receptacle, is developed. The fruit is most frequently a 1-seeded berry or drupe, or a nut which may be falsely berry-like, the partly persistent receptacle being fleshy and enveloping it.

This family appears the most nearly allied to the Frangulinæ, especially the Rhamnaceæ, and may be considered as a further development of these in the direction of the petaloid development of the receptacle and reduction of the corolla and gynœceum, which in this instance only consists of one carpel. Another deviation is that both the whorls of stamens are present, while one of these is always wanting in Frangulinæ. They also appear to be related to the Lauraceæ (see page 391).

Order 1. =Thymelæaceæ.= The flowers are most frequently ☿ (Fig. 483). The receptacle is high, generally tubular, coloured, and bears on its edge the 4-(or 5)-merous calyx, with imbricate æstivation. The corolla is wanting or is represented by small scales. The stamens are situated on the inside of the receptacle, and number 4 + 4 (or 5 + 5); stigma capitate. 1 pendulous ovule (Fig. 483 B), the radicle pointing upwards. The fruit is most frequently a berry. ~A disc is sometimes developed. Endosperm wanting or very slight.~

Daphne (Spurge-Laurel, Fig. 483) has a deciduous receptacle, often coloured; sepals 4; petals absent; stamens 4 + 4. Berry.--Gnidia (corolla); Pimelea (2 stamens); Thymelæa; Passerina and others.

400 species; chiefly in the warm, sub-tropical zone, especially the Cape and Australia. Only Daphne and Thymelæa in Europe. In the fruit and bark of some, for example Daphne, pungent, burning and poisonous properties are found. The bark of D. mezereum (native and cultivated) and D. laureola is officinal. A specially tough bast is found in some species, for example Lagetta lintearia (Lace-tree, Jamaica), which is used in weaving. Some are cultivated in gardens as ornamental shrubs, especially species of Daphne.

Order 2. =Elæagnaceæ.= Shrubs or trees, which are easily recognised by the covering of peltate hairs found upon almost all parts of the plant, causing them to assume a silvery or rusty-brown appearance. Stipules are absent; the leaves are simple, most frequently scattered. Flowers (Figs. 484, 485) frequently unisexual. The sepals are valvate, 2-4; the corolla is wanting; stamens 4 + 4 or 0 + 4. The ovule is erect and the radicle turned downwards (Fig. 486). The fruit is a nut, but becomes a false fruit, being surrounded by the persistent receptacle or the lower part of it, and thus assuming a berry- or drupe-like appearance (Fig. 486). Endosperm insignificant.--Shepherdia (opposite leaves) has 4 sepals, 4+4 stamens, as in Daphne. Diœcious.--Elæagnus (Silver-leaf) is ☿, has 4–6 sepals, and 4–6 stamens alternating with them. Hippophaë is diœcious; it has 2 sepals and 4 stamens in the ♂-flower (perhaps properly speaking 2+2 stamens); thorny (stem-structures).

16 species; especially ornamental shrubs, e.g. Elæagnus argentea, angustifolia; Hippophaë rhamnoides and Shepherdia canadensis. Northern Temp.

Order 3 (?). =Proteaceæ.= This order has its chief centre in the dry regions of Australia (6/10–7/10 of about 1,000 species), a smaller number in S. Africa (2/10–3/10). a few species in S. Am. Trees or shrubs, leaves generally scattered, without stipules, and more or less dry, leathery, evergreen, and often of very different forms on the same plant (undivided, compound, etc.) The flowers are ☿ (rarely unisexual), and 4-merous in the single, petaloid perianth and in the staminal whorl; 1 carpel; sometimes zygomorphic. The perianth-leaves are generally almost free, with valvate, æstivation, often leathery. Small scales alternating with the perianth are often found at the base of the ovary. The stamens generally have extremely short filaments, and are situated opposite, sometimes quite on the tip of the perianth-leaves, in a spoon-like groove. The gynœceum is 1-locular, has 1–several ovules, and is often raised on a stalk-like internode. The fruit is a follicle or nut. The seeds, most frequently winged, have no endosperm.--Protea, Manglesia, Hakea, Banksia, Grevillea, etc. 50 genera; about 1,000 species. Several species are cultivated in our conservatories for the sake of the flowers, which are beautifully coloured and arranged in crowded inflorescences. Protandrous. It is doubtful whether they were existent in Europe in the Tertiary Period. The true systematic position of the order is doubtful. They are related to the Leguminosæ and Rosifloræ, but more closely no doubt to the two preceding orders.

Family 19. =Saxifraginæ.=

The flower is generally perfect, regular and polypetalous, usually perigynous or epigynous, eucyclic and 5-merous; most frequently S5, P5, A5 + 5 or 5 + 0 and G=2=-5, but other numbers are found, especially 4; the flowers are very frequently obdiplostemonous. The calyx is sometimes large and the corolla small; the carpels in some are entirely free, in others more or less united. Endosperm is found in the majority. ~The hypogynous forms approach the Cistifloræ, the others the following families, especially the Rosifloræ. This family is not, upon the whole, so well defined and natural as most of the others. The Saxifragaceæ proper, approach very near to the Rosaceæ, especially Spiræa, and form a transition to it. The forms with opposite leaves, as Philadelphus, etc., approach the Myrtifloræ, just as the Escalloniæ appear to be closely allied to Bicornes, especially Vacciniaceæ. Finally through Pittosporaceæ, they pass over to the Frangulinæ. The family terminates in very reduced forms, on the one hand in the arborescent orders with crowded inflorescences, on the other perhaps in the very remarkable order Podostemaceæ.~

Order 1. =Crassulaceæ.= Nearly all are herbs or small shrubs with round, succulent branches and scattered, fleshy, often more or less round leaves, which are very rarely incised, and never have stipules. The flowers are generally borne in dichasia or unipared scorpioid cymes, which again may be arranged in racemes, umbels, etc.; they are regular, ☿, hypogynous or perigynous, and most frequently have free sepals and petals (gamopetalous corollas with sessile stamens are found in Cotyledon, Bryophyllum, Echeveria, and others); the floral formula is Sn, Pn, An + n, Gn, where n may have very different values, partly depending upon the size of the flower (e.g. 4–7 in Sedum, Fig. 487; 6–30 in Sempervivum; 4 in Rhodiola, Bryophyllum, and Kalanchoë; 5 in Echeveria, Umbilicus, Cotyledon). The carpels are free and are placed opposite the petals (Fig. 487). Fruit a syncarp composed of follicles containing many, small seeds without endosperm. Outside each carpel is found a small, nectariferous scale (Fig. 487). ~The northern genus, Rhodiola, is diœcious. The petal-stamens are wanting in some (Crassula, Bulliarda, and others). The floral-leaves are very often displaced upon their axillary branches. A multicarpellary gynœceum also occurs.~

Sedum (Stonecrop) is generally 5-merous with 10 stamens; Sempervivum tectorum (House-leek), 12-merous, and with 24 stamens. ~The leaves of Bryophyllum calycinum very readily form buds, and also frequently exude water from the edges.~

485 species; especially Temp. (Cape, Europe). Principally used as ornamental plants.

Order 2. =Saxifragaceæ.= The flowers are 4–5-merous with =2= (-3) carpels, most frequently: S5, P5, A5 + 5 (obdiplostemonous), G2. They are regular, ☿, polypetalous, hypogynous, perigynous or most frequently more or less epigynous (Fig. 488). The carpels may be individually quite free, but are more frequently united at the base, or the entire portion enclosing the ovules is united into a 1- or 2-locular ovary, the styles, however, are always free. Fruit a capsule with many seeds; endosperm present.--They are herbs, most frequently with scattered leaves without stipules; but the leaf-base is broad. The inflorescences are most frequently cymose, and a displacement of the floral-leaves is frequent (e.g. Chrysosplenium).--~Some Saxifraga-species, e.g. S. sarmentosa, have irregular flower with an oblique plane of symmetry. The petal-stamens in some may be wanting: Heuchera, species of Saxifraga and Mitella. The corolla is wanting in others.~

Saxifraga (Saxifrage): S5, P5, A5 + 5, G2 (Fig. 488); capsule bilocular, opening along the ventral suture between the 2 persistent styles. ~S. granulata has small tubers at the base of the stem.~--Chrysosplenium (Golden Saxifrage): 4 sepals, no corolla, 4 + 4 stamens; 1-locular capsule.

Protandry is most frequently found in Saxifraga, with the stamens successively bending towards the gynœceum; protogyny is more rare. In other genera there is protogyny without any movement of the stamens; Chrysosplenium is homogamous.--About 300 species; mostly in temperate climates. Saxifraga is especially Alpine. S. crassifolia and other species, Hoteia japonica, Tellima, etc., are ornamental plants.

The following genera are allied to the Saxifragaceæ:--

=1.= Parnassia (about 14 species; P. palustris, Grass of Parnassus). The flower is slightly perigynous, and has S5, P5, 5 fertile sepal-stamens, and 5 petal-stamens, which are developed as barren staminodes, palmately-lobed, and (3–) 4 carpels united in a 1-locular ovary with (3–) 4 parietal placentæ. Capsule.--~Protandrous. The flower has a slightly oblique plane of symmetry, which is especially shown during its development and in the order of sequence in which the anthers dehisce: originally they lie closely round the gynœceum; the anthers dehisce extrorsely, first the one which is placed opposite the most external sepal (the 2/5 arrangement is very distinct in the calyx), the filament elongating so that the anther lies over the ovary, and this is followed successively by the 4 others in a zig-zag line; the filaments bend backwards after the pollen is shed and the anthers drop off, and the stigmas are not developed until this is completed. The barren stamens are palmately divided into an uneven number (7, 9, 11) of lobes, tapering from the centre towards the edge, and bearing apparently glandular tips; their gland-like appearance is supposed to allure flies to visit the flower, or they may act as a kind of fence which compels the insects to enter the flower in a certain way, and thus effect pollination; the honey is secreted on their inner side, and not by the gland-like tips.~

=2.= Adoxa moschatellina (Moschatel). This is a perennial, creeping herb; the horizontal rhizome has an unlimited growth, and bears, in a scattered arrangement, both foliage-leaves, and white, fleshy scale-leaves. The aerial stem bears 2 opposite foliage-leaves and a capitate inflorescence of 5 flowers, 4 placed laterally (in opposite pairs) and 1 terminally. The flower is semi-epigynous, the calyx gamosepalous, corolla absent. The stamens are divided to the base, so that each filament bears a bilocular anther. The style is free, deeply cleft. The terminal flower has 2 bracteoles, 4 sepals, 4 stamens, cleft to the base, and a 4-locular ovary. The bracts of the lateral flowers are displaced on the flower-stalk, as in Chrysosplenium, and united with the 2 bracteoles into a kind of 3-leaved involucre; these flowers have 5 sepals, 5 split stamens with 2-locular anthers, and a 5-locular ovary. 1 pendulous ovule in each loculus. Fruit a drupe, green-coloured, with 1–5 stones.--This plant, which would perhaps be best placed in a special order, has also been classed with the Araliaceæ and Caprifoliaceæ.

The following are also allied to this order: Escalloniaceæ (arborescent plants with simple, scattered, leathery leaves), Cunoniaceæ (arborescent with opposite leaves), Cephalotaceæ (with pitcher-like, insect-catching leaves; Australia; Fig. 489) and Francoaceæ. These have respectively 85, 107, 1 and 3 species.

Order 3. =Ribesiaceæ= (=Currants=). 5-stamened Saxifragaceæ with epigynous flowers.--Moderately sized shrubs with scattered, stalked and palminerved, and generally palmilobed leaves, with a large leaf-sheath. The flowers (Figs. 490, 491), most frequently borne in racemes, are regular, epigynous, and have often, above the ovary, a cup- or bell-shaped, or tubular prolongation of the receptacle, on which the sepals, petals and stamens are situated; they have 5 sepals (often large, coloured), 5 small, free petals, only =5= stamens (opposite the sepals) and a =2=-carpellate gynœceum with a unilocular ovary and 2 parietal placentæ bearing many ovules. The fruit is a berry, whose seeds have a fleshy and juicy outer covering (Fig. 492). ~In some species, for example Ribes grossularia, there is found an unbranched, or a 3–5-branched spine, very closely resembling the spiny leaves of the Berberis, but which, however, are emergences springing from the base of the petiole. Ribes has two kinds of branches: long-branches and dwarf-branches, the latter alone bearing the flowers.~--Ribes (Figs. 490–492). The blades of the leaf are folded or rolled together in vernation. R. alpinum is diœcious.

75 species; especially from the N. Temp. regions (especially N. Am.).--The receptacle secretes honey on its inner surface. The Gooseberry-flower is slightly protandrous, others are homogamous; insect-and self-pollination are found. The following are FRUIT BUSHES: R. nigrum (Black Currant), R. rubrum (Red Currant), R. grossularia (Gooseberry), originating in Northern Europe and Asia. ORNAMENTAL BUSHES: the North American R. aureum (Golden Currant) and R. sanguineum (Blood-red Currant), etc.

Order 4. =Hydrangeaceæ.= Shrubs, with simple, opposite leaves, without stipules; flowers generally epigynous, 4–5-merous (Fig. 493).--Hydrangea (H. hortensia, etc.). Shrubs from N. Am. and E. Asia; corolla often valvate. The inflorescence, as in the case of the inflorescence of Viburnum opulus (Guelder Rose), has often irregular, large, but barren flowers at the circumference, whilst the others are much smaller, regular and ☿; the barren flowers are mostly 4-merous; in these cases it is the calyx which is large and petaloid, while the other parts of the flower are more or less suppressed. The branches of the inflorescence appear to be partially devoid of floral-leaves, since they are displaced upon the main axis.--Philadelphus; racemes (with terminal flower), sepals 4 (valvate), petals 4 (twisted), stamens many, and carpels 4 (opposite the petals), forming a 4-locular ovary. The numerous stamens (20–30) occur by the splitting of the sepal-stamens and are often therefore placed in distinct bundles. Fruit a capsule. Ph. coronaria (Syringa, Mock Orange-blossom), from S. Eur., is a common ornamental shrub, as also is Deutzia (Fig. 493) from N. Am. and E. Asia. The latter has S5, P5, A5 + 5, G3.--About 70 species.

Order 5 (?). =Pittosporaceæ.= This order has its home especially in Australia (90 species). The flower has S5, P5, A5 (episepalous), G2 (3–5), most frequently a unilocular ovary with many ovules in 2 rows, borne on 2 parietal placentæ, or a bilocular ovary. Some have berries, others capsules. Pittosporum, Citriobatus, Sollya, Billardiera.

Order 6. =Hamamelidaceæ.= Flowers more or less epigynous, with S4, P0 or 4, 4 fertile sepal-stamens, and 4 barren petal-stamens, bilocular ovary with 1–2 ovules in each loculus. Fruit a capsule. Hamamelis: one species in Japan and one in N. Am. Fothergilla. Liquidambar: monœcious; flowers in capitula or spikes; ♂-flowers without perianth, stamens indefinite; ♀-flower: slight perianth, 2-locular ovary with many ovules. OFFICINAL: “Styrax-balsam,” which is obtained by boiling the bark of Liq. orientalis, from Asia Minor. Liquidambar and Parrotia are found as fossils in the Upper Oligocene; Hamamelis perhaps in the Chalk.

Finally two orders with very reduced flowers are included in this family.

Order 7. =Platanaceæ.= Trees, with large, scattered, palminerved and lobed leaves, and ochreate stipules; the buds are concealed in a hollow at the base of the petiole. The bark falls off in large scales. ♂-and ♀-flowers (monœcious) in crowded, spherical inflorescences which are placed at wide intervals on a terminal, thin, and pendulous axis. The flowers have an insignificant calyx and corolla; the ♂-flower has few stamens; ♀-flower, perigynous, with 4 free carpels, 1 pendulous, orthotropous ovule in each. Fruit a nut; endosperm absent. 5 species; frequently grown in avenues and parks. P. occidentalis (N. Am.); P. orientalis (W. Asia.).

Order 8. =Podostemaceæ.= Aquatic plants, especially in swiftly running water, with somewhat of an Alga-like, Moss-like, or thalloid appearance; they show themselves in many ways to be adapted to their mode of life and situations (having a dorsiventral creeping stem, the flowers sunk in hollows, a formation of haptera upon the roots, and thalloid assimilating roots and thalloid stems, etc.). Tropical; 100 species.

Family 20. =Rosifloræ.=

The leaves are scattered, stipulate, or have at least a well developed sheath, which is generally prolonged on each side into a free portion (“adnate stipules”). The flowers are regular, perigynous or epigynous. Calyx and corolla 5 (-4)-merous with the usual position. The corolla is always polypetalous. The stamens are present in very varying numbers (5–∞) and position, but always placed in 5-or 10-merous whorls; they are frequently 20 in 3 whorls (10 + 5 + 5; see Figs. 494, 502, 505); the nearer they are placed to the circumference, the longer they are; they are generally incurved in the bud, or even rolled up. The number of the carpels is from 1–∞; in most cases all are individually free (syncarp), and when they are united it is in every case with the ovaries only, whilst the styles remain more or less free (Pomaceæ, species of Spiræa). The seeds have a straight embryo, and usually no endosperm.

The perianth and stamens are most frequently perigynous on the edge of the widened receptacle; its form varies between a flat cupule and a long tube or a cup (Figs. 495, 496, 498, 499, 500); the carpels are situated on its base or inner surface, in some instances on a central conical elongation of the floral axis (Fig. 496). The carpels in Pomaceæ also unite more or less with the hollow receptacle, or this grows in and fills up the space between the carpels, so that a more or less epigynous flower is formed (Fig. 504).--The following numbers of stamens occur: 5, 10 (in 1 whorl), 15 (10 + 5), 20 (10 + 5 + 5), 25 (10 + 10 + 5), 30-50 (in 10-merous whorls)--compare the diagrams. The theoretical explanation of this relation of the 10-merous whorls and their alternation with the 5-merous whorls is not definitely determined; a splitting of the members of the 5-merous whorls may be supposed, but the development shows no indication of this, and it is not supported in any other way. Several genera have “gynobasic” styles, that is, the style springs from the base of the ovary (Fig. 497 A, B).

The Rosifloræ are on one side closely related to the Saxifragaceæ (especially through Spiræa) from which it is difficult to separate them, and to the Myrtifloræ; on the other side they are allied, through the Mimosaceæ with the large number of stamens, and through the Amygdalaceæ with its single carpel, to the Leguminosæ. The family begins with forms which have many-seeded follicles, and passes on the one side to forms with nuts and drupes in perigynous flowers, and on the other side to the Pomaceæ.

Order 1. =Rosaceæ.= Herbs or shrubs, generally with compound leaves and persistent (adnate) stipules, flower perigynous, gynœceum formed of many free (therefore oblique) carpels, syncarps with fruitlets of various kinds. The exceptions are noted under the genera.

=1.= SPIRÆEÆ (Fig. 495) has 2–many ovules in each ovary, while in the other groups there is generally only 1, and never more than 2 ovules in each loculus. There are generally 5 cyclic carpels and the fruit is 5 follicles, which are not enclosed by the receptacle. The majority are shrubs. Stipules are often wanting.--Spiræa (Meadow-Sweet). The flowers are generally borne in richly flowered inflorescences of various forms. The carpels, in some species, unite together and form a simple gynœceum with free styles (an approach to the Pomaceæ).--~Closely allied to Spiræa are the East Asiatic shrubs: Kerria japonica, which has solitary flowers, in this country nearly always double (the fruit a nut), and Rhodotypos kerrioides which has opposite leaves, a remarkable feature among the Rosifloræ; it has a 4-merous flower, a well developed disc inside the andrœcium, and a drupe. Closely allied also is Gillenia (N. Am.) differing chiefly in the ascending ovules, Spiræa having pendulous ovules, and a more tubular receptacle.~

The groups Quillajeæ and Neuradeæ form a transition from Spiræa to Pomaceæ. In the first group, which contains only trees or shrubs with generally simple leaves, the carpels are either free or united (into a capsule); in the second the receptacle unites with the carpels, which are themselves often united together; in this case, too, the fruit is a capsule. Quillaja (S. Am.); Exochorda (China).

=2.= POTENTILLEÆ (Figs. 494, 496, 497). The flower has an “epicalyx” (Fig. 494 C) alternating with the sepals and formed by their stipules which are united in pairs, and hence its leaves are often more or less deeply bifid. The receptacle is cupular and often quite insignificant. The sepals are valvate in the bud. The large number of fruitlets are achenes, borne on a well-developed convex portion of the receptacle (~the Ranunculeæ resemble the Potentilleæ, but have no epicalyx, no enlarged receptacle, and spirally-placed stamens~). Most of the species are herbs with dichasial inflorescences, often arranged in racemes.--Potentilla (Cinquefoil). The achenes are borne on a dry, hairy receptacle; the style is situated towards the apex of the ovary, and is not prolonged after flowering. Herbs with digitate, in some, however, pinnate leaves, and generally yellow flowers.--Comarum (Fig. 494) (Marsh Cinquefoil) forms, by its fleshy-spongy receptacle, a transition to the next genus.--Fragaria (Strawberry) (Fig. 496). The receptacle becomes finally fleshy, coloured, and falls off (biologically it is a berry); the numerous fruitlets (drupes with thin pericarp) have basal styles (Fig. 497); leaves trifoliate; long, creeping runners.--Geum (Avens) has a terminal style which after flowering elongates into a long beak, with the apex (after the uppermost part has been thrown off) bent back into a hook, thus furnishing a means of distribution for the fruits. Leaves pinnate.--~Dryas comprises 3 Arctic or Alpine species with simple leaves and solitary flowers, the calyx and corolla 8–9-merous, the fruit resembles that of Geum, but the styles become still longer and feather-like (a flying apparatus).~

=3.= RUBEÆ. Rubus (Bramble) has the same form of receptacle as the Potentilleæ, but no epicalyx; the fruitlets are drupes, not enclosed by the persistent calyx. Most frequently shrubs or undershrubs with prickles (emergences), glandular bristles and compound leaves. In the Raspberry (R. idæus) the fruitlets unite together and detach themselves from the receptacle.

=4.= ROSEÆ. Rosa; the receptacle is hollow, ovoid and contracted beneath the insertion of the calyx (Fig. 498), ultimately fleshy and coloured; it encloses a large number of fruitlets which are achenes as hard as stones (“hip,” biologically a berry).--Shrubs with imparipinnate leaves and adnate stipules. ~The sepals show clearly the order of their development (a divergence of 2/5), the two outer ones on both sides are lobed, the third one on one side only, and the two last, whose edges are covered by the others, are not lobed at all. Prickles (emergences) are generally present and in some species are placed in regular order, being found immediately below each leaf (usually two) although at somewhat varying heights.~

=5.= AGRIMONIEÆ. The receptacle is more or less cup- or bell-shaped, and almost closed at the mouth; it is persistent and envelopes the nut-like fruitlets, but is dry, and in some species hard, the fruitlets being firmly attached to it. In biological connection with this the number of the carpels is generally only 1 or 2, and the whole becomes a false nut (Fig. 500). Herbs.--Agrimonia (Agrimony; Figs. 499, 500); the perianth is 5-merous, stamens 5–20. The receptacle bears externally, on the upper surface, a number of hooked bristles which serve as a means of distribution for the 1–2 achenes which are enclosed in it, and hence the entire flower finally falls off. The inflorescence is a long upright raceme. ~These bristles are arranged in whorls of 5 and 10, of which the uppermost alternate with the sepals.~--Alchemilla (Ladies-mantle; Fig. 501) has 8 green perianth-leaves in two whorls (some authorities consider the four outer as an epicalyx, and the flower therefore apetalous), and 4 stamens alternating with the innermost whorl. There is only one carpel with a basal style and capitate stigma. The flowers are small and greenish, the filaments jointed. The anthers open by one extrorse cleft. The leaf-sheath entirely envelops the stem; the leaves are palminerved. A. aphanes has often only 1–2 stamens. ~The following genera, with 4-merous flowers borne in short spikes or capitula, are allied to this group. Sanguisorba has entomophilous, ☿-flowers with 4(-20) stamens, 1 carpel; stigma papillose.--Poterium; spike or capitulum, the uppermost flowers are ♀, the lowermost ♂, and some intermediate ones ☿ (the order of opening is not always centripetal); S4, P0, A20–30, G2, the long styles having brush-like stigmas (wind-pollination). Leaves imparipinnate.~

POLLINATION. A yellow ring on the inner side of the receptacle, inside the stamens, serves as a nectary when any honey is formed; this, for instance, is not the case in Rosa, Agrimonia, Spiræa ulmaria, S. filipendula, S. aruncus, etc., to which the insects (especially flies and bees) are allured by the quantity of pollen. Homogamy and slight protogyny are frequent, in many instances self-pollination also is finally possible. Poterium, with the long-haired stigma, is wind-pollinated.--About 550 (1100?) species, especially in northern temperate regions.--USES. OFFICINAL: the petals of Rosa centifolia and gallica, the fruits of the Raspberry (Rubus idæus), the rhizome of Geum urbanum, the flowers of the Koso-tree (Hagenia abyssinica or Brayera anthelmintica).--The bark of Quillaja saponaria (Chili) is used as soap and contains saponin. “Attar of Roses” from Rosa damascena, centifolia and other species, especially from the southern slopes of the Balkans. Many species and varieties of Roses are ORNAMENTAL plants: from S. Europe, Rosa lutea (the Yellow Rose), R. gallica (the French Rose) and R. rubrifolia; from W. Asia, R. centifolia, of which the Moss Roses (R. muscosa and cristata) are varieties, and R. damascena; from India and N. Africa, R. moschata (the Musk Rose); from China, R. indica (Tea Rose) etc., besides the native species and the varieties which have been derived from them. In addition, Kerria japonica, species of Potentilla, Rubus odoratus from N. Am., and many species of Spiræa from South-eastern Europe and N. Am. ESCULENT: the “hips” of R. mollissima, R. pomifera, etc.; the fruits of Rubus-species: Raspberry (R. idæus), Cloudberry (R. chamæmorus), Blackberry (R. fruticosus), etc.; of Fragaria-species (F. vesca, collina, grandiflora, etc).

Order 2. =Amygdalaceæ.= Trees or shrubs with rosaceous flowers; leaves simple with caducous stipules; a regular, perigynous flower, the receptacle being partly thrown off by a circular slit; sepals 5, petals 5, stamens 20–30; gynœceum simple, formed of 1 carpel (hence oblique, Fig. 502), with terminal style and 2 pendulous ovules, ripening into a drupe (Fig. 503).--The leaves are penninerved and frequently have glands on the stalks and edges; thorns (modified branches) often occur, i.e. dwarf-branches, which, after producing a few leaves, terminate their growth in a thorn (e.g. Prunus spinosa). ~The vernation of the foliage-leaves varies in the different genera; in the Almond, Peach, Cherry, and Bird-Cherry they are folded; in the Apricot, Plum, Sloe and Bullace, rolled together. In some the flowers unfold before the leaves (Amygdalus, Armeniaca). That the gynœceum is formed of 1 carpel is evident in this as in other instances (e.g. in the Leguminosæ, which are closely related to this order), from the fact that the carpel is oblique, and has only one plane of symmetry, and similarly in the fruit there is a longitudinal groove on one side which indicates the ventral suture. It is only exceptionally that both ovules are developed. In abnormal instances more than 1 carpel is developed.~

=A.= FRUIT HAIRY: Amygdalus (A. communis, Almond-tree) has a dry pulp which is detached irregularly, when ripe, from the wrinkled, grooved, ovoid and somewhat compressed stone.--Persica (P. vulgaris, Peach-tree) differs from the Almond in having a juicy pulp, not detachable from the stone, which is deeply grooved and has pits in the grooves (Fig. 503). (~The name of the genus is derived from Persia, though it is a native of China.~).--Armeniaca (A. vulgaris, Apricot) has a hairy, velvety fruit, but the stone is smooth and has two ribs along one of the edges; the pulp is juicy. (~The generic name has been given on the incorrect assumption that it was a native of Armenia; its home is China.~)

=B.= FRUIT GLABROUS (i.e. without hairs): Prunus (Plum) has a glabrous fruit with bluish bloom; the stone is compressed, smooth or wrinkled. The flowers are borne solitarily or in couples, and open before or at the same time as the leaves; they are borne on shoots without foliage-leaves.--Cerasus (Cherry) has a glabrous, spherical fruit, without bloom, and a spherical stone. The flowers are situated in 2–many-flowered umbels or racemes, and open at the same time as the leaves or a little before them. ~Long-stalked flowers in umbels are found in C. avium (Wild Cherry), C. vulgaris (the cultivated Cherry, from Western Asia); racemes at the apex of leaf-bearing branches and small spherical fruits are found in C. padus (Bird Cherry), C. virginiana, C. laurocerasus (Cherry-laurel), C. mahaleb.~

POLLINATION. Prunus spinosa (Sloe, Blackthorn) is protogynous, but the stamens are developed before the stigma withers. Honey is secreted by the receptacle. Cerasus padus (Bird-Cherry) agrees in some measure with P. spinosa. In the flowers of the Plum and Cherry the stamens and stigma are developed simultaneously and self pollination seems general; the stigma, however, overtops the inner stamens and thus promotes cross-pollination.--DISTRIBUTION. 114 species in the N. Temp, zone; few in the warmer regions; the majority from W. Asia. C. vulgaris, from the regions of the Caspian; Prunus spinosa, insititia (Bullace), domestica (Plum, from the Caucasus, Persia).--USES, principally as fruit-trees: Cherry, Plum, Apricot, etc.; “Almonds” are the seeds of Amygdalus communis (W. Mediterranean), “bitter,” “sweet,” and “shell” almonds are from different varieties, the latter being remarkable for the thin, brittle stone. In the majority of species and in almost all parts of the plant (especially the bark, seed and leaves) is found the glycoside, amygdalin, which forms prussic acid. Many form gum, and the seeds have fatty oils (“Almond oil”). OFFICINAL: the seeds and oil of Amygdalus communis, and the fruit of the Cherry; in other countries also the leaves of C. laurocerasus.--The stems of Cerasus mahaleb are used for pipes. Ornamental Shrubs: Amygdalus nana, Cerasus laurocerasus.

Order 3. Chrysobalanaceæ. Tropical Amygdalaceæ with zygomorphic flower and gynobasic style. 200 species; especially Am. and Asia. Chrysobalanus icaco (Cocoa-plum) is cultivated on account of its fruit (Am.)

Order 4. =Pomaceæ.= Trees and shrubs, most frequently with simple leaves and caducous stipules. The flowers (Fig. 505) have 5 sepals, 5 petals and generally 20 stamens (10 + 5 + 5, or 10 + 10 + 5). There are from 1–5 carpels, which unite entirely or to some extent with each other, and with the hollow, fleshy receptacle (the flower becoming epigynous), (Figs. 505, 506, 507). The carpels are nearly always free on the ventral sutures, rarely free at the sides also. The whole outer portion of the fruit becomes fleshy, but the portions of the pericarp surrounding the loculi (endocarp) are most frequently formed of sclerenchymatous cells, and are more or less firm (the “core”). The nature of the fruit varies, according to the thickness and hardness of the endocarp, being either a “berry” or a “drupe” (see A and B). When the endocarp is thin and parchment-like, the fruit has the characteristics of a berry, each of the 5 loculi generally present containing several seeds; but when this is hard the fruit resembles a drupe, only one seed is developed in each loculus, and the number of the loculi is reduced to one or two. There are nearly always 2 ovules in the loculi of the ovary, but in Cydonia there are a large number in 2 rows. In the genera which have stones, only one seed is developed in each stone. The genera are distinguished mainly in accordance with the kind of fruit and the number of ovules and seeds.

=A.= SORBEÆ. THE ENDOCARP IS PARCHMENT-LIKE OR PAPERY (drupe, with thin stone or berry).

1. Pyrus and Cydonia; carpels completely embedded in the cup-like receptacle, styles always free.--Pyrus: the fruit is glabrous, and has only a small calyx, withering or deciduous, and a 5-locular ovary with at most 2 ascending ovules in each loculus (Fig. 504 D). The large flowers are situated in few-flowered umbels or corymbs. ~P. communis (Pear; free styles, Fig. 507; it has the well-known pear-shaped fruit; the core is reduced to several groups of sclerenchymatous cells embedded in the pulp, the leaf-stalk is as long as the blade).~--Cydonia (Quince) has a hairy fruit with many seeds in 2 rows in each loculus of the endocarp (Figs. 504 C, F; 506); the testa of these seeds is mucilaginous. C. vulgaris, large, terminal flowers on lateral branches, and large leaf-like, persistent sepals.

2. Malus and Amelanchier (Aronia); carpels free on the ventral edge; styles united. Malus communis (Apple) the fruit is “umbilicate” at the base; no sclerenchymatous cells in the pulp; styles united at the base (Fig. 504 D); leaf-stalk shorter than the blade. Sorbus (Mountain-ash) differs only in having a 2–3-locular fruit with extremely thin endocarp. Cymose inflorescences in umbellate cymes. ~S. aucuparia has pinnate leaves, S. aria (White-beam) and other species have simple leaves.--Amelanchier (the Service-tree) has a false divisional wall springing from the dorsal suture, and more or less projecting into each of the loculi of the ovary; Raphiolepis (Fig. 504 E) has racemes and a juicy berry; Eriobotrya japonica (Loquat).~

=B.= CRATÆGEÆ. THE ENDOCARP IS HARD AND BONY (“drupes,” generally with several, sometimes, however, with only 1–2 stones, rarely one multilocular stone; only 1 seed in each of the loculi).--Cratægus (Hawthorn, May). There are 1–5 stones in the spherical or ovoid fruit. The disc, found on the apex of the fruit, inside the small, withered calyx, is small (much less than the transverse section of the fruit). Shrubs with thorns (branches) and moderately large flowers borne in corymbs.--Mespilus (Medlar) differs from the last-named only in having a large disc at the apex of the fruit, inside the large, leaf-like sepals, i.e. almost equal to the greatest diameter of the fruit. The flowers are solitary and terminal.--Cotoneaster is chiefly distinguished from the others by its syncarps, the 2–5 carpels (and stones) being free from one another, and only united to the receptacle by a larger or smaller portion of their dorsal surface (Figs. 504 A, B). Small shrubs with leathery leaves, generally covered with white, felted hairs on the lower surface, and with small flowers; the fruit is red or black.

Pear, Apple, Mountain Ash and Hawthorn have protogynous flowers which secrete honey, and are conspicuous to ensure insect pollination.--180 species; in the northern temperate regions.--Pear and Apple are especially cultivated as fruit trees in a number of varieties; the Paradise Apple (Pyrus baccata); especially in southern countries also the Quince (from N. Persia and the Caucasian districts), Medlar and Amelanchier vulgaris. Malus pumila (Caucasus, Altai) and M. dasyphylla (Orient, S. Eur.) are regarded as primitive forms of the Apple-tree; M. sylvestris, which grows wild in European forests, appears to have been less used. The early Lake-dwellers in Switzerland had the apple-tree both wild and cultivated.--The original form of the Pear is supposed to be Pyrus achras (Central Asia).--Many of the species of Cratægus, some with double flowers, and Pyrus (Chænomeles) japonica, with brilliant red flowers, are cultivated as ornamental shrubs. OFFICINAL: Quince pips, on account of the mucilaginous testa.--The fruits contain free organic acids and sugar; prussic acid may be obtained from the seeds. The wood of the Pear-tree is used in manufactures.

Family 21. =Leguminosæ.=

The most characteristic feature is, that the gynœceum is 1-locular and formed of 1 carpel, the ventral suture of which is turned posteriorly. The fruit, in most instances, is a pod (legume), which opens generally along both sutures, the two valves twisting more or less in opposite directions. ~In other instances it opens along one suture only, or as a pyxidium (Red Clover), or it is indehiscent, in which case it is more or less berry-like (e.g. the Tamarind, Carob-bean), or it is a drupe (e.g. the Tonquin-bean), or a 1–few-seeded nut (e.g. Melilotus), or a lomentum, which divides transversely into as many joints as there are seeds (Ornithopus, see Fig. 513).~

The inflorescences belong to the centripetal type (i.e. indefinite); cymes do not occur. The flowers are zygomorphic, with vertical plane of symmetry, seldom regular; 5-merous with but a few exceptions, ☿, and slightly perigynous. The following diagram is the most general (Fig. 511): 5 sepals, with the unpaired sepal median and anterior, 5 petals, 5 + 5 stamens, all in alternating whorls, 1 carpel. The calyx is most frequently gamosepalous, the gynœceum is narrowed down at the base to a short stalk and, in the majority, is more or less bent. The seed is most frequently kidney-shaped, with a smooth, hard and shining testa, the hilum being very distinct. Endosperm is wanting, or is reduced to a thin layer, which is of service when the seed swells during germination. The vegetative parts have these features in common, namely, the leaves are scattered, stipulate, and almost always compound. Peculiar sleep-movements and sensitiveness are found in some, chiefly in the Mimosas. Many, probably all, Leguminosæ have small tubercles on their roots which are produced by a kind of bacterium, and assist in the assimilation of free nitrogen. Spontaneous movements are exhibited by Desmodium gyrans (Telegraph-plant).

This family is closely allied to the Rosifloræ, with which it agrees in the scattered leaves, the presence of stipules, the generally 5-merous and most frequently perigynous flowers with eucyclic stamens, and the absence of endosperm. Amygdalaceæ and Chrysobalanaceæ, with solitary carpels, approach on one side to the Leguminosæ, among which genera with drupes are also found; Mimosaceæ, with their many stamens, form a connecting link on the other side. In this respect the Mimosa-genus Affonsea, and certain Cæsalpineæ and Swartzieæ, are of special interest in having more than one carpel (syncarp), a condition which is sometimes met with abnormally in other Leguminosæ, as well as in Amygdalaceæ. About 7,000 species of the Leguminosæ are known.

Order 1. =Cæsalpiniaceæ.= These are leguminous plants with straight embryo and a flower which is not papilionaceous and has not the same æstivation (Figs. 508–510); but in reality there is not a single characteristic which absolutely distinguishes them from the Papilionaceæ.--The majority are arborescent; the leaves as a rule are pinnate or bipinnate. The flower is 5-merous, most frequently perigynous and slightly zygomorphic; the calyx is free or gamosepalous, the corolla polypetalous with ascending imbricate æstivation (i.e. the two lowest petals envelop the lateral ones, and these again the posterior; Fig. 508); 10 free stamens; fruit various.

Cassia (Figs. 508–510) is the largest genus (about 200 species); it has an almost hypogynous, zygomorphic flower with 5 free sepals and petals; of the 10 stamens the 3 posterior are generally barren, the others are of very unequal length and open at the apex by pores (Fig. 509). In some (the Senna group) the fruit is a flat, short, thin, dehiscing pod; in others (Cathartocarpus) it is round, long, woody or fleshy, indehiscent, and divided internally by more or less fleshy transverse walls into as many cells as there are seeds.--The following also have DEHISCENT FRUITS: Bauhinia (often lianes, tropical climbers with tendrils [stem-structures] and anomalous stems), Copaifera, Hæmatoxylon (whose pod does not dehisce along the suture, but laterally), Cercis (simple leaves; the corolla resembles that of the Papilionaceæ, but the posterior petal is the smallest, and is enveloped by the 2 lateral ones, which are enveloped in their turn by the 2 anterior).--FRUIT INDEHISCENT: Tamarindus indica; the pod is almost round, often a little abstricted between the seeds; the wall is formed by a thin, brittle external layer, enclosing an acid pulp; well-developed septa are present, between the seeds; the most internal layer is parchment-like. Calyx 4-merous by the coalescence of 2 sepals. Only 3 fertile stamens.--Ceratonia siliqua (Carob-bean, Locusts); the pod is long, compressed, with thick sutures, and has a wall, the central part of which is more or less leathery, fleshy and sweet; there are transverse septa between the seeds, as in the Tamarind. Embryo greenish in endosperm. The flower is without a corolla, 5 stamens.--Pterogyne (winged fruit), etc.--KRAMERIEÆ with Krameria is an anomalous group.

DISTRIBUTION. 80 genera, with 740 species; almost exclusively in the Tropics. The Carob-tree and Cercis grow in the Mediterranean basin. The largest and most widely distributed genus is Cassia, which is found as trees, shrubs, and weeds in all tropical countries. The order has many important uses to mankind. MEDICINAL: the leaves and pods of Cassia acutifolia and angustifolia (officinal, Senna-leaves), the fruit-pulp of the Cassia-sub-genus, Cathartocarpus. Rhatany root from Krameria triandra (Peru, officinal). Balsam is extracted from a number of Copaifera-species (Balsam of Copaiba) from S. Am. (officinal), and from Hymenæa (Copal balsam), Trachylobium and others. Edible fruits are obtained especially from the Carob-tree (from the East) and the Tamarind (officinal). The heart-wood of several species of Cæsalpinia, such as C. brasiliensis (the Pernambuco-tree), echinata (Red-tree), and sappan, yield dyes; Hæmatoxylon (H. campechianum, Logwood), Copaifera bracteata (Amarant-tree).--Timber is obtained from many (Melanoxylon and others). In Europe they are of little importance as ornamental plants, these being confined principally to the species of Gleditschia (G. triacantha, from N. Am.) and Cercis (the Judas-tree, C. siliquastrum, S. Eur.), which are cultivated in gardens; but in tropical gardens beautiful flowering species, e.g. of Cassia, Poinciana, Brownea, are found, and the most beautiful of all ornamental plants, the Indian Amherstia nobilis.

Order 2. =Papilionaceæ.= The flower (Figs. 511, 512) is strongly zygomorphic and somewhat perigynous (Fig. 512 B; most frequently more on one side than the other). The calyx is gamosepalous and persistent. The polypetalous corolla has descending imbricate æstivation, the posterior, large leaf, the standard (Figs. 511 f; 512 B’, e), covering in the bud the two lateral ones, the wings (Figs. 511 v; 512 B’, a), which again cover the two anterior; these are united in the form of a boat, the keel (k and c); the wings and the two petals of the keel are very unsymmetrical. That the keel is formed of two petals is seen by its position (in front of one sepal) and by the two often more or less free claws. The 10 (5 + 5) stamens (monadelphous) are either all united into one bundle, or into two bundles (diadelphous), the posterior one being free (Fig. 512 C). The ovules are curved and also the embryo (Fig. 512 G), especially the hypocotyl, so that the radicle assumes a position close to the edge of the thick, fleshy cotyledons. Endosperm wanting; the cotyledons are very rich in proteid reserve material. The forms of the fruit and exceptions are described under the genera.

Geocarpic fruits, i.e. those which penetrate the soil during their development and ripen underground, are found in e.g. Arachis hypogæa (see page 472), Trifolium subterraneum, Vicia amphicarpæa. Germination takes place in various ways. In the majority the cotyledons are raised above the ground as green, leaf-like bodies; in the Vicieæ they remain thick and white, and are always enclosed in the testa, and are therefore never able to take part in the work of assimilation; in species of Phaseolus, on the other hand, they are raised well above the ground and become green, but remain however thick and fleshy.

=1, 2.= The two groups PODALYRIEÆ (the majority of the genera are Australian) and SOPHOREÆ (Sophora, Edwardsia, etc.), represent the oldest type, as they have 10 free stamens and so form the transition to the Cæsalpiniaceæ. Nearly all are trees and shrubs.

=3.= ASTRAGALEÆ. Herbs or shrubs, less frequently trees, with imparipinnate leaves (without tendrils). The flowers are generally borne in racemes or spikes. Stamens monadelphous or diadelphous.--Astragalus (Milk-Vetch) has the legume incompletely divided longitudinally into 2 loculi by a septum formed by the incurved dorsal suture. Diadelphous.--Glycyrrhiza (Liquorice); Colutea (Bladder-Senna) from S. Europe; Robinia (the false Acacia) with thorny stipules; Indigofera (the Indigo plant); Amorpha (which has only one petal, namely the standard, and the fruit a nut), Caragana, Wistaria (a climbing shrub), Galega. Carmichælia australis, when old, produces flat branches with scale-like leaves.

=4.= VICIEÆ. Climbing herbs with paripinnate leaves, the midrib ending in a point or frequently in a tendril, which generally is branched, representing lateral veins without mesophyll; stamens diadelphous; the cotyledons remain underground on germination.--Vicia (Vetch) has a filamentous style, hairy towards the tip, and a pod with many seeds; climbing by means of tendrils; the leaves have many leaflets.--Faba (F. vulgaris, Horse-bean) is erect, without tendrils; its pod is thick with spongy septa between the seeds.--Ervum (Lentil) has a pod with only 1–2 seeds, and sweeping hairs (stylar-brush) on the inner side of the style.--Pisum (Pea; Fig. 512) has very large stipules, the bent style has a hollow groove on the anterior side. P. sativum (Common Pea), P. arvense (Grey Pea).--Lathyrus (Sweet Pea) generally has an angular, winged stem and most frequently only a few pairs of leaflets. The style is flattened, with sweeping hairs on the back. ~In L. aphaca the stipules alone are developed into foliage-leaves, while the remainder of the leaf is modified into a tendril.~--Cicer has a nearly straight embryo and imparipinnate leaves with dentate or incised leaflets. C. arietinus (Chick-pea).--~Abrus (precatorius, etc.); the seeds (“Crab’s eyes,” “Paternoster peas,” “Jequirity”) are scarlet with a black spot round the hilum.~

=5.= PHASEOLEÆ. Herbs, twining or erect, but not climbing by tendrils; the leaves are imparipinnate, generally ternate, and bear small, linear bodies resembling stipules at the base of the stalks of the leaflets. The inflorescences are most frequently compound, groups of few flowers being situated on short, nodose, lateral axes borne on a longer stem. On germination the cotyledons are raised a considerable distance above the ground, and become greenish, but do not become leaf-like; in P. multiflorus they remain underground. Stamens as in the Vetches.--Phaseolus (Kidney-bean): the keel with the stamen and style is spirally twisted (to the right). Herbs, twining to the left.--~The “Calabar-bean” (Physostigma venenosum), Erythrina, Clitoria, Glycine, Soja, Mucuna, Apios, Canavalia, Vigna, Dolichos, Cajanus, Rhynchosia, etc.~

=6.= TRIFOLIEÆ (CLOVERS). Herbs with ternate leaves, the leaflets are often dentate with the veins prolonged into the teeth; stamens diadelphous; fruit 1-locular, 1–few-seeded, pyxidium-like, irregularly dehiscent, or more frequently a nut. The flowers are generally borne in capitula, racemes, or spikes.--Trifolium (Clover). The corolla is gamopetalous. The calyx persists, together with the corolla, round the ripe fruit. The inflorescence is a spike, capitulum or capitate umbel; the leaves are ternate, and have adnate stipules.--Medicago (Medick). The corolla falls off after flowering; fruit curved like a sickle or spirally twisted; it is a nut, and opens with difficulty. Leaves ternate.--Melilotus (Melilot) has a small, spherical or lanceolate, thick and wrinkled fruit, which as a rule is indehiscent. The inflorescence is a raceme, often long, or a spike, sometimes a capitulum. Leaves ternate.--Ononis (Rest-harrow) differs in having monadelphous stamens and in being more shrub-like and bushy, and in having a normal, 2-valved pod, by which characteristic it approaches the Genisteæ. The flowers are generally rose-coloured, solitary, or in few-flowered racemes in the leaf-axils. Thorns (branches) are often present; the leaves are compound with only one small leaflet (the terminal one), or ternate with adnate stipules.

=7.= LOTEÆ. Herbs with ternate or imparipinnate leaves, with entire leaflets. In the latter case, when the lowest pair of leaflets is placed quite close to the sheath, the stalk is wanting, and apparently a trifoliate leaf with large stipules is developed. Flowers in an umbel or capitulum. Stamens monadelphous or diadelphous, the filaments (either all of them, or only the 5 sepal-stamens) are widened at the top.--Lotus (Bird’s-foot-trefoil) has a long, round pod.--Tetragonolobus.--Anthyllis (Lady’s-finger); the fruit is a nut, which is distributed by the wind by means of the membranous, bladder-like calyx, which completely encloses and falls off with it.

=8.= GENISTEÆ. The majority are shrubs or trees with apparently simple leaves, i.e. compound leaves with only one leaflet (the terminal leaflet), or ternate leaves; the stipules in most instances are very small or are entirely wanting; stamens monadelphous.--Genista (Dyer’s-weed) has apparently simple leaves; the branches often terminate in a thorn. ~The strongly-winged stems in G. sagittalis are its most important organs of assimilation. Bossiæa rufa has flat branches, its leaves being reduced to small, pointed stipules.~--Sarothamnus (Broom) has switch-like, angular branches and often both the apparently simple and ternate leaves on the same shoot; style spirally rolled.--Cytisus (Laburnum). Ulex (Furze; ~in U. europæus, the seedlings bear a few foliage leaves, but the leaves succeeding these are modified into thorns~); Spartium; Crotalaria, etc.--Lupinus (Lupin) is allied to this group; it has a thick, often somewhat fleshy pod, and digitate leaves with adnate stipules.--Retama.

=9.= HEDYSAREÆ are especially recognised by having the ovary divided by transverse septa into as many cells as there are seeds, the fruit thus becomes a lomentum, dehiscing transversely into nut-like joints (Fig. 513).--Ornithopus (Bird’s-foot); Coronilla; Hippocrepis; Onobrychis (Sainfoin) has a fruit with only 1 joint (i.e. a 1-seeded nut); Desmodium; Alhagi; Hedysarum, etc.--Arachis hypogæa (Earth-nut) has a pod which is abstricted between the seeds, and is indehiscent, but is not multilocular nor a true lomentum; it is reticulately wrinkled externally, and ripens underground; the basal part of the ovary is prolonged after flowering, attaining a length of several inches, and buries the young fruit in the soil. The embryo is straight.--~Desmodium gyrans is well-known for its motile leaflets.~

=10.= DALBERGIEÆ. 25 genera; especially in Tropical America; the majority are trees, a few shrubs or lianes; the leaves are simple or imparipinnate. The fruit is indehiscent in all; in some it is a winged, in others a wingless nut (Machærium, Dalbergia, Centrolobium, etc.), in others, again, a drupe, e.g. in Dipteryx (Tonquin-bean) and Andira. In some genera the embryo is straight.

POLLINATION. Especially effected by Bees. The nectar is secreted by a ring or disc-like portion round the base of the gynœceum or the inner surface of the receptacle. The flower is constructed with a peculiar mechanism to ensure cross-pollination by insects. The pollen is shed just before the flower opens, and is retained in a pouch formed by the keel. An insect visiting the flower uses the wings and keel for a landing-stage, and in attempting to reach the honey presses down the wings and the keel which are locked together near the standard; the stylar-brush by this means is forced through the apical opening of the keel and a little pollen is thus swept out and deposited upon the abdomen of the visiting insect as it presses against the apex of the keel; the insect thus carries away pollen and may effect cross-pollination. In the different flowers this arrangement is modified in various ways to promote pollination. 5000 species (319 genera); especially in the Tropics, where many are important forest trees.--The following plants are used FOR FOOD: Pisum sativum (W. Asia?) and arvense (Italy); Phaseolus vulgaris (Kidney-bean, American; Dolichos sinensis was known to the Greeks and Romans under the name “φασηλος,” “phaseolus”), P. compressus (French-bean), etc.; Faba vulgaris (Field-bean, Horse-bean; from the Old World); Ervum lens (Lentil, Eastern Mediterranean); in tropical countries the oil-containing seeds of Arachis hypogæa.--The following are FODDER plants: Vicia sativa, Faba vulgaris, Onobrychis sativa (Sainfoin), Medicago sativa (Lucerne), and lupulina (Medick), species of Trifolium, Hedysarum coronarium. OFFICINAL: “Liquorice root,” from Glycyrrhiza glabra (S. Europe); “Red Sandalwood,” from Pterocarpus santalinus (Tropical E. Asia); Gum Tragacanth, from Astragalus-species (E. Mediterranean); Balsam of Peru, from Toluifera pereiræ, and Balsam of Tolu, from Toluifera balsamum. Calabar-beans, from Physostigma venenosum; Kino, from Pterocarpus marsupium; the pith of Andira araroba is used under the name of “Chrysarobin.”--Of use TECHNICALLY: Genista tinctoria (yellow dye) and Indigofera-species (Indigo), the bast of Crotalaria juncea (Sunn Hemp); the seeds of Dipteryx, which contain Coumarin, and are highly scented, and Balsam of Myroxylon. POISONOUS: the seeds of Laburnum (Cytisus laburnum), various species of Lathyrus, and Abrus precatorius; the latter contain two poisonous proteids, paraglobulin and albumose, which resemble snake-poison in their effects. The following are ORNAMENTAL plants: Phaseolus multiflorus (Scarlet runner, from America), Robinia pseudacacia, Amorpha, Colutea, Coronilla, Indigofera dosua, Wistaria polystachya, Cytisus laburnum (Laburnum, S. Europe, Orient.) and other species.

Order 3. =Mimosaceæ.= The flowers are most frequently hypogynous and regular, the æstivation of the corolla is valvate and, in the majority of instances, that of the calyx also. The flower is 4-merous, less frequently 5- or 3-merous.--The flowers are generally small, but are always borne in compact, round capitula or spikes (Fig. 514); they are hypogynous or perigynous. The calyx is generally gamosepalous and the corolla gamopetalous, the latter being frequently wanting. The stamens are equal or double the number of the petals (Mimosa, etc., in M. pudica, e.g. S4, P4, A4, G1) or (in Acacia, Inga, etc.) in a large, indefinite number, free or monadelphous, often united to the corolla (Fig. 514 b). The colour of the flower in most cases is due to the long and numerous stamens. The fruit is various. The embryo is straight as in the Cæsalpiniaceæ. Entada and many species of Mimosa have a flat, straight, or somewhat sickle-like pod, which resembles the siliqua of the Cruciferæ in that the sutures (in this instance, however, dorsal and ventral suture) persist as a frame, but the intermediate portion divides, as in the transversely divided siliqua, into as many nut-like portions as there are seeds. Some species have a pod of enormous dimensions. The seeds of Entada gigalobium are often carried from the West Indies to the N. W. coasts of Europe by the Gulf Stream.--The fruit of Acacia in some species is an ordinary pod, in others it is transversely divided, or remains an undivided fruit, a nut.--This order includes both trees and herbaceous plants, which are often thorny; the leaves are usually bipinnate (Fig. 514) and are sensitive, and also possess sleep-movements.--Many Australian Acacias have compound leaves only when young, but when old have phyllodia, i.e. leaf-like petioles without blades, placed vertically. A large number have thorny stipules, which in some (Acacia sphærocephala) attain an enormous size, and serve as a home for ants, which in return protect their host-plant against the attacks of other, leaf-cutting ants.

Other genera besides those mentioned are: Adenanthera, Desmanthus, Parkia, Inga (with rather fleshy, indehiscent fruit), Calliandra, etc.

1350 species (30 genera); none natives of Europe, their home being the Tropics and sub-tropical regions, especially Australia and Africa.--Fossils in Tertiary.--Gums are found in many species of Acacia, especially the African (Gum arabic) and Australian, of which some are officinal. The bark, and also the fruits, contain a large amount of tannic acid and are used as astringents and in tanning (“Bablah” is the fruits of several species of Acacia). Catechu is a valuable tanning material extracted from the wood of Acacia catechu (E. Ind). The flowers of Acacia farnesiana (Fig. 514) are used in the manufacture of perfumes. With us they are cultivated as ornamental plants, e.g. A. lophantha and many others, in conservatories.

Family 22. =Passiflorinæ.=

The flowers are most frequently regular, 5-merous in the three most external whorls, eucyclic and perigynous or epigynous, less frequently hypogynous. A characteristic feature is that the ovary is tricarpellary, unilocular, and with 3 parietal placentæ which sometimes meet in the central line (Cucurbitaceæ). The styles are generally free and bifid. To all these characteristics, however, there are exceptions. ~The Cucurbitaceæ are sometimes placed among the Sympetalæ, close to the Campanulinæ, but they are not allied to the Sympetalæ, from which they differ especially, for instance, in the structure of the ovule. The position of the Begoniaceæ in this family is also open to doubt.~

Order 1. =Passifloraceæ= (=Passion-flowers=). The majority are herbs which climb by means of tendrils (modified branches) and have scattered, stipulate leaves, often palminerved and lobed (Fig. 515). The flowers, which are often large and beautiful, are regular, ☿, with S5, P5, A5, G3; the calyx and corolla are perigynous, and immediately inside the corolla is the “corona,” consisting of numerous, tapering, filamentous bodies, or sometimes united in rings, most frequently petaloid and coloured; the stamens are raised on a long, round internode above the cup-like receptacle; immediately above these is the gynœceum with its 3 free styles and capitate stigmas; the ovary is unilocular with 3 parietal placentæ. Fruit most frequently a berry. The seeds have an aril.

210 species; especially in Tropical America. Several Passiflora-species are ornamental plants, and the fruits of some species are edible.

Order 2. =Papayaceæ.= The best known representative is the Papaw (Carica papaya), a Tropical American tree whose stem is usually unbranched, and bears at its summit several large, palmilobed leaves on long stalks. The stem and leaves have latex. The large, Melon-like berries are edible, and for this reason it is cultivated in the Tropics. Flowers unisexual, with slightly different structure in the ♂-and ♀-flowers, besides intermediate forms. The ♂-flower has a gamopetalous, the ♀-flower a polypetalous corolla.--The milky juice contains a substance with similar action to pepsine. 10 stamens. 5 carpels.

Order 3. =Turneraceæ.= 85 species; especially in America.

Order 4. =Samydaceæ.= 160 species; tropical.

Order 5. =Loasaceæ.= Herbaceous plants seldom shrubs, sometimes climbing, and nearly always studded with stiff hairs, in some instances stinging or hooked. The leaves are most frequently palmilobed and without stipules. The flowers are regular, ☿, polypetalous, entirely epigynous, with 4–5 sepals, petals and stamens, or more frequently (by splitting) many stamens, those which are placed before the sepals being generally barren and more or less petaloid; carpels most frequently 3, united into an inferior, unilocular ovary with 3 parietal placentæ, above which the receptacle is generally more or less prolonged. Fruit a capsule; in Gronovia an ovary with 1 ovule and fruit a nut.

115 species; principally from S. Am. A number of annuals are often grown in our gardens: Bartonia aurea (California); Mentzelia; Cajophora; Gronovia.

Order 6. =Datiscaceæ.= 4 species, especially in the Tropics.--Datisca cannabina (Asia Minor) resembles the Hemp in external appearance. The flowers are diœcious, insignificant; ♂-flowers: a low, gamosepalous calyx, no corolla, and an indefinite number of stamens; ♀-flowers; epigynous; ovary unilocular with free, mostly bifid, styles, and generally 3 parietal placentæ. In most cases the ovary is not entirely closed at the top (as in Reseda).

Order 7. =Begoniaceæ.= This order principally comprises herbs or under-shrubs with succulent stems (having scattered vascular bundles in the pith); the leaves are arranged in two rows (a divergence of 1/2) and are asymmetrical, as a rule more or less obliquely cordate, or ovate with cordate base (Fig. 516); large, caducous stipules are present. Inflorescences dichasial, or unipared scorpioid cymes; the flowers are unisexual; the first ones (the oldest) are ♂-flowers, while ♀-flowers are found especially on the younger axes. The ♂-flowers have most frequently 2 + 2 coloured perianth-leaves, and many stamens collected into a head in the centre of the flower; the ♀-flowers are epigynous with 5 coloured perianth-leaves (placed spirally with a divergence of 2/5) and a trilocular ovary, bearing 3 bifid styles and 3 wings (the wings usually of unequal size); in the inner angle of each loculus there is one large projecting placenta, or two plate-like placentæ (the bent back edges of the carpels) studded with ovules. Fruit a capsule, with many extremely small seeds.--Begonia.

420 species; almost all from the Tropics (Am., Asia).--Many species, with varieties and hybrids, are ornamental plants in houses and conservatories, chiefly on account of the form, colour and markings of their leaves; but also for their very beautiful flowers. They reproduce easily by adventitious buds from leaves and portions of leaves placed on damp soil; some have bulbils. Like the Oxalideæ they contain an acid sap.

Order 8. =Cucurbitaceæ.= The flower is epigynous, and, as a rule, is also provided with a leaf-like, cup- or bell-shaped receptacle above the ovary, to which the perianth and stamens are attached; the flowers are regular, unisexual, with rudiments of the other sex, and 5-merous: sepals 5, narrow and pointed, with the median sepal posterior (Fig. 517), petals 5, stamens 5, and carpels 3 (rarely 4–5); the corolla is gamopetalous in the majority, polypetalous in some; generally plicate-valvate in the bud. The anthers in the ♂-flowers are extrorse, and monothecious, i.e. only one half of each of the anthers of the 5 stamens is developed, the pollen-sac having frequently a peculiar [tilde]-shaped curve (Fig. 518 A, B); the stamens are either all united into a column (e.g. in Cucurbita), or they are united in pairs, so that only one remains free (Figs. 517 A; 518 A); in the latter case there appears to be one small stamen with a [tilde]-shaped, curved pollen-sac and two larger ones, each with two curved pollen-sacs placed as in Fig. 517 A. The original form appears to be Fevillea with free petals and 5 free stamens. Sometimes the rudiment of a gynœceum is present. The carpels are united into an ovary with 3 (4–5) placentæ formed by their united edges. These are thick, fleshy, and bifid, bearing a number of ovules on each side (Figs. 517 B; 518 C, D); in general the placentæ are so large that they not only meet in the centre, but also fill up the ovary as far as the wall of the pericarp. The whole interior of the fruit thus becomes a juicy mass in which three lines may be seen, meeting in the centre (the boundaries of the individual placentæ), and near the circumference 6 groups of seeds (Fig. 518 D). When the carpels are equal in number to the petals they alternate with them. The style is short and thick, and generally divided into 3 (4–5) branches, with a horse-shoe shaped stigma on each branch (Fig. 518 C). The fruit is most frequently a many-seeded berry; in some it attains a considerable size and has a firm external layer (Cucurbita, Lagenaria, etc.). The embryo is straight, has no endosperm, but contains a large quantity of oil. The exceptions to the above characters will be found under the genera.

Exclusively herbs, generally with stiff hairs and yellow flowers. Many species are annuals, others are perennial, having tuberous roots or hypocotyls. The leaves are scattered, long-stalked, in most cases more or less heart-shaped, palminerved, palmilobed, and exstipulate; in their axils are found both flowers (singly, or in an inflorescence) and a vegetative bud, and outside the axil, on the anodic[37] side of the leaf, a simple or branched tendril, by which the plant climbs (exceptions: e.g. Ecballium).

The position of the flowers, branches and tendrils situated in and near the leaf-axils is as follows. In the leaf-axils, a flower is borne (as a branch of the first order), ♂ or ♀, according to the conditions of the various genera. This branch is not situated in the centre of the axil, but is removed slightly towards the anodic side of the leaf. Of its two bracteoles as a rule only the one lying on the anodic side is developed, namely as a tendril, which is displaced to a position outside the axil. The branch of the first order bears on its catodic side an inflorescence (in the axil of the suppressed bracteole), on the anodic side a vegetative bud which grows out into a branch like the main axis. The subtending leaf of this branch is thus the tendril; but when it has several arms the condition is complicated by the appearance of an accessory bud which unites with its subtending leaf, the tendril, its leaves also becoming tendrils (situated on an undeveloped internode); the many-branched tendril is thus a branch, and the tendril-arms are its leaves, except the main arm which is its subtending leaf. Other explanations of these difficult relations have been given.--The germination is somewhat peculiar, owing to the fact that a heel-like prolongation is formed at the base of the hypocotyl to assist in separating the two halves of the testa from each other, and to facilitate the unfolding of the cotyledons.

Cucurbita (Pumpkin, Marrow) has branched tendrils; the flowers are monœcious, and are borne singly; the corolla is bell-shaped, and divided almost as far as the middle. The stamens are all united into a tube; the compressed seeds have a thick, blunt edge.--Cucumis has (generally) unbranched tendrils; the ♀-flowers are borne singly, whilst the ♂-flowers are borne in groups: the corolla is divided nearly as far as the base, and the stamens are united 2-2-1. The connective is elongated above the anthers. The seeds have a sharp edge.--Citrullus (Fig. 518) has a corolla similar to Cucumis, but ☿-and ♂-flowers are borne singly; the stigma is only 3-lobed, the fruit most frequently spherical.--Ecballium (Squirting Cucumber, only 1 species, E. elaterium) has no tendrils, and is therefore not a climber. The oblong fruit is pendulous from the apex of its stalk, and when ripe is distended with an acrid, watery fluid; on being touched the fruit is detached, and the seeds, together with the watery fluid, are violently ejected through the aperture formed at the base of the fruit. The ♂-flowers are borne in racemes near the solitary ♀-flowers (Fig. 517).--Bryonia (White Bryony) has chiefly unbranched tendrils and small, greenish-yellow, usually diœcious flowers with rotate corolla, in many-flowered inflorescences; the small, spherical berry has no specially firm outer layer, and generally only few seeds. The tap-root and a few of the other roots are tuberous. B. alba (berry black; monœcious) and dioica (berry red; diœcious). ~Among other genera may be mentioned: Lagenaria (Gourd); the fruit has a woody external layer which, after the removal of the pulpy integument, may be used as a gourd. Luffa has a polypetalous corolla; the fruit is dry, and consists internally of a network of vascular bundles; it opens by an aperture at the summit. Benincasa; the fruit has a close, bluish coating of wax. Trichosanthes (Snake Cucumber) has a thin, round, long and curved fruit. Momordica; the fleshy fruit opens and ejects the seeds. Cyclanthera takes its name from the staminal column which is found in the centre of the ♂-flower, bearing a bilocular, ring-like anther which opens by a horizontal cleft. The fruit is unilocular by suppression, has 1 placenta, and when touched opens and ejects the seeds. Sicyos and Sechium have only unilocular ovaries with one pendulous ovule. Sechium has, moreover, 5 free stamens, of which only one is halved, the other 4 having both halves of the anther. Fevillea and Thladiantha also have 5 free stamens. Dimorphochlamys has dimorphic flowers.~

POLLINATION is effected by insects, chiefly bees or wasps, the nectar being secreted by the inner, yellow portion of the receptacle; in the ♂-flower access is gained to the nectar through the slits between the stamens, which arch over the nectary.--85 genera; about 637 species; especially in the Tropics. Only two are found in the whole of N. Europe, Bryonia alba and dioica; in S. Europe, Ecballium also. Most of the cultivated species have been obtained from Asia, such as the Cucumber, Melon, Colocynth, several Luffa-species (the “Gourds” mentioned in Scripture are Cucumis chate); from Africa, the Water-melon, Cucurbita maxima, and others; from S. Am., no doubt, the Pumpkin (C. pepo and melopepo). USES. Many species are used in medicine or for domestic purposes. Bitter, poisonous properties are found; the fruits of the two officinal ones are purgative: Citrullus colocynthis (Mediterranean, E. India, Ceylon) and Ecballium elaterium, as well as various tropical species, the roots of Bryonia, etc.--The following are cultivated AS ARTICLES OF FOOD: Pumpkin (Cucurbita pepo, etc.), Cucumber (Cucumis sativus), Melon (Cucumis melo), the Water-melon (Citrullus vulgaris), Sechium edule (Chocho), certain species of Luffa (the young fruit). The Bottle Gourd is cultivated in tropical countries for the sake of its hard pericarp, which is useful for bowls, bottles, etc. The fruits of Luffa have a number of reticulately felted, tolerably firm vascular bundles, which render them serviceable in various ways (as a kind of “sponge”). The Cucurbits are of no use in the manufactures. Only a few are cultivated as ornamental plants, chiefly as curiosities.

Family 23. =Myrtifloræ.=

The leaves are most frequently opposite, simple, entire (rarely dentate), and exstipulate. The flowers are regular and epigynous (perigynous in Lythraceæ and a few others), ☿, polypetalous; the number of members in a whorl is generally 4 or 5 (S, P, A, or most frequently A 2, G), but sometimes it becomes (e.g. Myrtles and Lythraceæ) very large in the andrœcium by splitting, and in the gynœceum also is often different. (When suppression takes place it is principally in the corolla and petal-stamens.) In nearly all instances the calyx is valvate. Gyncœceum multicarpellary, multilocular, with only one style (except Haloragidaceæ). In the majority the ovules are situated on an axile placenta in the multilocular ovary. Endosperm is wanting in the majority.--~Less important exceptions: Rhizophoraceæ and Gunnera have stipules. Haloragidaceæ have several styles and endosperm. Rhizophora also has endosperm.~

Order 1. =Lythraceæ.= Hermaphrodite, perigynous flowers which are most frequently =6=-merous, viz. S 6 (often with a commissural “epicalyx,” Fig. 519 c), one segment posterior, P 6, A 6 + 6 or 6 + 0 and G =2–6=, forming a 2–6-locular ovary with many ovules in the loculi, style single, and capitate stigma. The gynœceum is free at the base of the tubular, or bell-shaped, thin, strongly veined receptacle, which bears the other leaf-whorls on its edge and inner side. Fruit a capsule. No endosperm.--To this order belong both herbs, shrubs and trees. The branches are frequently square, the leaves always undivided, entire, and without stipules, or with several very small stipules, and often opposite. The calyx is valvate. The flower is regular (except Cuphea) and frequently large and beautiful. The stamens are generally incurved in the bud, and the petals irregularly folded.

Lythrum (Loose-strife). The flower is diplostemonous and 6-merous, with a long, tubular receptacle with epicalyx-teeth (Fig. 519 c). The 12 stamens are arranged in two tiers on the inner side of the receptacle. The gynœceum is bicarpellary. ~The flowers are borne in small dichasia in the leaf-axils, and their number is increased by accessory inflorescences beneath the main inflorescence.--The native species, L. salicaria, is trimorphic (long-styled, mid-and short-styled forms, Fig. 520). Cross-pollination is chiefly effected by humble-bees and bees, which seek the nectar formed at the bottom of the receptacle. Other species are only dimorphic, or even monomorphic.~--Closely allied are, Nesæa, Diplusodon, Lagerstrœmia, and Cuphea, whose flower resembles that of Lythrum, but is zygomorphic. In Cuphea the receptacle is oblique and at the back prolonged into a spur, in which the nectar, secreted by a gland situated behind the ovary, is collected; the calyx and corolla gradually become reduced in size toward the anterior side of the flower; the reverse, however, is the case with the 11 stamens (the posterior one is absent); the posterior loculus in the bilocular ovary is sometimes barren; the fruit, when ripe, dehisces along the posterior side, the ovary as well as the wall of the receptacle being ruptured by the placenta, which expands and projects freely. ~The flowers stand singly in the centre of the stem, between the pairs of leaves. This may be explained as follows: of the two foliage-leaves in each pair, one supports a foliage-shoot, the other a flower; the foliage-shoot remains in the axil, but the flower is displaced through the length of an entire internode to the next pair of leaves, and then assumes a position between these two leaves. All foliage-shoots stand in two rows, the flowers in two other rows.~

Peplis (Water-purslane), a small, annual plant, with thin, bell-shaped receptacle without projecting nerves. The small flowers have no petal-stamens, and often also no corolla; fruit indehiscent.--Ammannia is closely allied to it.

365 species; 30 genera; mostly in the Tropics, and more especially S. Am.--Some yield dyes, e.g. Lawsonia inermis (cultivated in Africa and Asia) and Lagerstrœmeria indica; some contain tannin; others are ornamental plants, especially in gardens in warm countries.

Order 2. =Blattiaceæ.= 12 species. Tropical Asia and Africa. Trees. Formerly included with Punica, but best placed as an independent order.

Order 3. =Melastomaceæ.= A very natural and very large order (150 genera; 2,500 species), its home being chiefly in tropical S. America, especially the Brazils (termed by Schouw “The kingdom of Palms and Melastomaceæ”). There are both herbaceous and arborescent species, which are easily recognized by the opposite or verticillate, simple leaves which have (with the exception of a few heather-like species) 3–5–7–9 curved veins proceeding from the base of the leaf, and connected very regularly by closely parallel, transverse veins. The flower is perigynous or epigynous; its type is that of the Onagraceæ (4–5-merous; 1 whorl of sepals, petals and carpels, 2 of stamens); the calyx is valvate, the corolla is twisted (to the left) in æstivation; the stamens are very characteristic; in the bud they are geniculate; the anther opens in the often long, beak-like, prolonged point, with 1, less frequently with 2 pores, and has generally ear-like appendages at its base. The fruit is a berry or capsule. These large and beautiful flowering-plants play a very important part in South American landscapes; otherwise they are of slight importance (a few are cultivated in conservatories, e.g. Centradenia, Medinilla, Lasiandra, Tibouchina, Miconia, etc.).

Order 4. =Œnotheraceæ= (or =Onagraceæ=). The flowers are arranged in racemes or spikes, ☿, epigynous, regular, polypetalous, =4=-merous in all 5 whorls (1 whorl of sepals, petals and carpels, 2 of stamens); 2–3–5–6-merous flowers are less frequent; the calyx is valvate, the corolla twisted in æstivation (the left edge being covered). Gynœceum simple with multilocular ovary; the style is undivided, filiform, and bears a capitate or 4-partite stigma; endosperm wanting; embryo straight.--The majority are herbs, especially water- and marsh-plants; several are shrubs. No essential oils. The leaves are alternate or opposite, always single, and without (or with very small) stipules. ~The odourless flowers sometimes have a coloured calyx. In some instances (e.g. Œnothera, Fuchsia) the receptacle is prolonged more or less beyond the inferior ovary, and finally falls off. The stamens are obdiplostemonous (carpels epipetalous); the petal-stamens are sometimes suppressed. The anthers in some genera are divided into storeys. The well-pronounced, triangular pollen-grains are connected together by viscous threads. Small stipules are sometimes found, e.g. Fuchsia, Lopezia.~

=A.= =Fruit a capsule.= Œnothera (Evening Primrose) is 4-merous, has 8 stamens, a tubular receptacle, and an oblong capsule with loculicidal dehiscence leaving a centrally placed column, bearing the seeds.--Epilobium (Willow-herb) deviates from Œnothera especially in the seeds being hairy (at the chalazal end of the seed).--Chamænerium is a Willow-herb with zygomorphic flowers.--~The following may be included here: Clarkia, Eucharidium (an Œnothera with 4 stamens and 3-lobed petals), Godetia and Boisduvalia, Jussiæa (dehiscence septicidal), Isnardia (petal-stamens absent, sometimes the petals also).--Lopezia has a peculiar, zygomorphic flower (Fig. 521); one of the four sepals is bent forwards and the other 3 backwards; the posterior petals are narrower than the 2 anterior ones which are turned obliquely backwards and bent like a knee, with a greenish nectary at the bend; 2 stamens, one only fertile (the posterior), while the anterior is barren, petaloid, and spoon-shaped; both are sensitive, which is essential for pollination. In Fig. 521, a represents an early stage, in which the stamen and style lie concealed in the staminode; b is the ♂ stage, the stamen projects from the centre of the flower; c, the ♀ stage, the style occupies the place of the stamen.~

=B.= =Fruit a berry.= Fuchsia generally has a coloured calyx and tubular receptacle; the corolla may be wanting.

=C.= =Fruit a nut.= Circæa (Enchanter’s Nightshade) has a 2-merous flower (S2, P2, A2 + 0 [petal-stamens are wanting], G2). The flowers are borne in racemes without bracts.--Gaura.

=D.= =Fruit a drupe.= Trapa (Horn-nut); a peculiar aquatic plant; the submerged stem has long internodes and lanceolate leaves, falling off at an early period, but at each node are found 4 long roots with thin, lateral roots (sometimes erroneously regarded as leaves) borne pinnately; the stem reaching the surface of the water, bears a rosette of rhombic foliage-leaves, with large, inflated stalks containing air, and forming the floating apparatus of the plants. In the axils of the leaves (as in Gunnera) 8 small, stipular structures are present. The flowers are solitary in the axils of the foliage-leaves (S4, P4, A4 + 0, G2), semi-epigynous. There is an 8-lobed, crenate disc on the free portion of the ovary; one ovule in each loculus. The fruit is a drupe with 4 (or 2) prominent horns (the persistent sepals), which after the pulp has decayed away bear a series of hooks turned downwards on each side, i.e. sclerenchymatous bundles which formerly lay concealed in the pulp of the sepals. ~The germination is peculiar: one of the cotyledons is large, and its thick extremity remains in the fruit, the other however is small and is pushed out at the apex of the fruit together with the radicle and plumule; the development of the root soon ceases, and the plumule usually grows into a stem entirely without branches, similar to the one described above, only that 1–2 precisely similar shoots arise in the axil of each cotyledon, so that each embryo produces 3–5 shoots.--Trapa, by its mode of life, its 1-seeded fruit, etc., forms a transition to Haloragidaceæ.~

The large-flowered forms are adapted for insect-pollination and are often protandrous, the small-flowered ones are homogamous and may pollinate themselves. Œnothera is adapted for hawk-moths and bees.--330 species; especially in temperate climates, chiefly in the Northern Hemisphere. Epilobium, Circæa are natives of this country; Trapa is extinct in this country, it has been found in a semi-fossilized condition near Cromer and in bogs in Denmark, and existed in Sweden until a few years ago; Œnothera has been introduced from N. Am.--A number of N. Am. species are grown as ornamental plants in our gardens. The seeds of Trapa natans are edible, and used as food in China.

Order 5. =Haloragidaceæ.= This is a reduced form of the Œnotheraceæ, and principally differs from these in the presence of endosperm and free styles. Only 1 ovule in each loculus.--84 species distributed over the entire globe; the majority are aquatic plants. The most advanced type is Myriophyllum (Water-Milfoil), with a regular, epigynous flower (S4, P4, A4 + 4, G4), most frequently diclinous (monœcious); the fruit is a 2–4-partite schizocarp. Aquatic plants, most frequently with pectinate, pinnate leaves.--Haloragis.--~Gunnera (a dozen species from the Southern Hemisphere) forms the next step in the reduction. Large, scattered, rough-haired, and softly-spined leaves, with small flowers in crowded inflorescences. The flower, when most complete, has S2, P2, A2 (petal-stamens) and G2, forming an inferior, unilocular ovary with 1 ovule. It is remarkable for the great number of stipules placed in transverse rows in the leaf-axils, for the peculiar glandular organs, and for the colonies of Nostoc, which are found embedded in the cortex as a kind of parasite.~--The simplest form is Hippuris (Mare’s-tail) with an extremely small, crenate or entire calyx, without corolla, and with only one stamen and one carpel, forming an inferior, unilocular ovary with only one ovule. Fruit a drupe with thin pulp. ~It is an aquatic plant with creeping, sympodial rhizome, and erect unbranched shoots, bearing numerous small, verticillate leaves. The small flowers are situated singly in the leaf-axils.~

Order 6. =Rhizophoraceæ.= Tropical trees or shrubs (50 species, the best known being Rhizophora mangle, Mangrove) which grow gregariously, especially along the banks of rivers and by sea-coasts, where the water is quiet and brackish, and where they form the so-called Mangrove-swamps. Aerial roots are formed on the stems and branches (Fig. 522 A). The seeds germinate in the fruit, which by arrest contains only one seed (Fig. 522 B), before it is detached from the tree. The radicle projects considerably from the seed, and hangs down freely in the air; when the embryo is finally detached from the mother-plant, the separation is effected by the hood-like cotyledon, which entirely envelops the plumule, becoming detached from the rest of the embryo, which falls down, while the hood-like cotyledon remains enclosed in the fruit. The embryo, after it has fallen, strikes root, and continues growing in the undisturbed mud under the trees, or perhaps it may first be drifted about by the water, being well adapted for this by its peculiar, tough nature, and large, intercellular spaces.--It may also further be remarked that the anther is divided into a number of small loculi. The leaves are stipulate. The endosperm projects from the micropyle, growing out from the base of the seed, and thus serves as an organ of suction to convey nutriment to the embryo from the mother-plant.

Order 7. =Combretaceæ.= Trees and shrubs, partly lianes. An inferior, unilocular ovary with few pendulous ovules. Conocarpus and Laguncularia form, in conjunction with the species of Rhizophoraceæ, the tropical Mangrove-swamps. Terminalia.--280 species; Tropics.

Order 8. =Myrtaceæ (Myrtles).= The plants belonging to this order are shrubs or trees, the majority being easily recognised by the vegetative characters. The leaves, for instance, are most frequently opposite, without stipules, undivided and entire, parchment-like or leathery, evergreen, aromatic, finely dotted by pellucid glands containing essential oils; the venation is penninerved with a nerve just inside and running parallel to the edge of the leaf. The flowers are regular, epigynous (Figs. 523, 524, 525) and ☿, most frequently =4-= or 5-merous in the calyx and corolla, with many stamens (by splitting, so that they are often in several distinct bundles) and an ovary with one style, formed of 2–5–many carpels; the receptacle is most frequently united for its entire length with the ovary. The fruit varies, but is most frequently a berry. The embryo is thick, often curved, with united cotyledons; no endosperm.

=1.= MYRTEÆ, MYRTLE GROUP. Chiefly American, though some are found also in Africa and Asia. The fruit is a berry with generally 2–5 loculi in the ovary, and many ovules in each.--Myrtus; Eugenia (the petals fall off together as a hood in the Clove, E. caryophyllata, Figs. 523, 524); Myrcia; Jambosa; Amomis; Psidium, etc.

=2.= PUNICEÆ, POMEGRANATE GROUP. Only 2 species (Punica granatum; from Persia, Afghanistan), differing in several respects from the typical form of the Myrtaceæ. The leaves are generally opposite, without glands and marginal veins. The receptacle, calyx and corolla are red; the latter 5–8–(generally 6-) merous. Calyx valvate and corolla folded as in Lythraceæ, stamens also and epicalyx as in this order. The most characteristic feature is the inferior, spherical berry, with dry pericarp, formed from two whorls of carpels in two tiers (Fig. 525); the interior whorl, which is also the lower, has 3 carpels, and the placentæ are situated in the inner angles of the 3 loculi; the external whorl is 5-merous, and the placentæ have originally the same position in the inner angles of the loculi, but their position is changed to the outer side of the loculi owing to the growth of the wall of the ovary, which takes place early, causing the carpels to become, as it were, turned inside out, so that the part which was turned downwards is turned upwards, and the part which was turned inwards becomes turned outwards (as in Mesembrianthemum). The edible part of the fruit is the fleshy testa, as in Ribes. The cotyledons are rolled together spirally.

=3.= LECYTHIDEÆ. The majority are South American. The leaves are scattered, without pellucid glands, and frequently dentate. The flowers are zygomorphic. The woody fruits are either indehiscent, or open by a lid. To this belong: Bertholletia (B. excelsa), the seeds well known as “Brazil-nuts,” Lecythis (Sapucaia-nuts from L. ollaria), Barringtonia.

=4.= LEPTOSPERMEÆ. Almost entirely from Australia and the East Asian and Pacific Islands. The fruit is a capsule. The leaves are scattered, and in some placed edgewise by the twisting of the leaf-stalks.--Eucalyptus, the Australian Gum-tree; the calyx falls off like a lid (Figs. 526, 527). Some of the species attain gigantic heights, E. amygdalina 140–150 m. with a diameter of 8 m. The leaves in E. globulus are opposite and dorsiventral on the young plant; on the older scattered, placed edgewise by the twisting of the leaf-stalk, and isolateral; Metrosideros, Calothamnus (stamens distinctly polyadelphous), Melaleuca, Leptospermum, Callistemon (the flowers are borne in spikes whose axis continues to grow after flowering, thus several zones of fruits may be seen on the same branch).

=5.= CHAMÆLAUCIEÆ. Australian shrubs with heath-like appearance; they differ from the other Myrtaceæ in having a unilocular ovary with few, basal ovules, and a 1-seeded nut. The sepals are often pappus-like, and divided into many bristles.--Chamælaucium, Darwinia, etc.

This large order (2,100 species) is confined almost entirely to the Tropics, being found principally in America and Australia. In Europe, only Myrtus communis.--Several are useful on account of the large quantity of volatile oils (contained in internal glands): the flower-buds (“Cloves”) of Eugenia caryophyllata (the Moluccas, cultivated in the Tropics, Figs. 523, 524); the unripe, dry berries (“Pimento”) of Myrtus pimenta (Pimenta officinalis, W. Indies); Cajeput oil is extracted from Melaleuca minor and leucadendron (East Asian Islands). Eucalyptus globulus (Australia) has of late years become well known on account of its rapid growth, its hard wood, and its antipyretic qualities; it is cultivated on swampy soils, which it helps to drain.--OFFICINAL: “Cloves,” and the cork of both stem and root of Punica granatum. Several have EDIBLE FRUITS, such as Psidium guyava (Guava, var. pomiferum and pyriferum, Am.), Eugenia cauliflora and others, E. jambosa, Punica granatum (the Pomegranate), etc. EDIBLE SEEDS (with abundance of fatty oil): “Brazil nuts” from Bertholletia excelsa (Trop. S. Am.). “Bay-rum” is extracted from the leaves and fruits of the Bayberry-tree (Pimenta acris, W. Ind.); Guava-rum from the berries of Eugenia floribunda. Tannin is found in large quantities e.g. in Punica. Gum is formed by many Australian Eucalypti (“Gum-trees”). ORNAMENTAL PLANTS cultivated in this country are: Myrtus communis (Mediterranean), several in conservatories, especially the Australian Leptospermeæ, Eucalyptæ and others.

Family 24. =Umbellifloræ.=

The flower is regular, ☿, and completely epigynous, 5- or 4-merous, with =1= whorl of stamens and 5–2 carpels. Sepals very small, tooth-like. The corolla is polypetalous, most frequently valvate in æstivation (least pronounced in the Umbelliferous plants). Round the base of the styles, which are generally free, there is an epigynous (undivided, or divided) nectar-disc (“stylar-foot”: Figs. 528 B, C, D; 539); the number of loculi in the ovary equals that of the carpels; only =1= pendulous (anatropous) ovule (Fig. 528 C) in each loculus. Endosperm copious (Fig. 528 D). To this must be added that the inflorescence in the majority of cases is an umbel or a capitulum, especially in the Umbelliferæ and Araliaceæ. Stipules are absent, but most frequently the base of the petiole forms a large sheath.

The Umbellifloræ are on one side so closely allied to the Frangulinæ, especially Rhamnaceæ, that they may perhaps be regarded as the epigynous continuation of this family. On the other hand, the similarities to the Rubiales, especially those between Cornaceæ and Sambuceæ, are so great that there is scarcely any character to distinguish them except the polypetalous corolla of the former and the gamopetalous corolla of the latter. Whether this is more than a merely analogous resemblance, and if not, whether the Cornaceæ at least should not be included in the Rubiales, must be left in abeyance.--The sepals are very small, as is generally the case in epigynous flowers.

Order 1. =Cornaceæ.= The majority of the species are shrubs with solid internodes, opposite (rarely scattered) leaves, which are simple, entire (rarely incised), penninerved, without stipules or large sheaths; flowers =4=-merous (most frequently S4, P4, A4, G2), borne in dichasia which are either collected into corymbs (e.g. Cornus sanguinea), or in closely crowded umbels or capitula (Cornus mas, C. suecica), in which latter case there is often a large, leafy, or coloured, most frequently 4-leaved involucre round the base of the inflorescence; the style is undivided, with lobed stigma; the raphe of the ovule is turned outwards. The fruit is a berry or a drupe, with a 1–4-locular stone or 2 free stones.

Cornus (Dogwood, Cornel) has S4, P4, A4, G2. Leaves opposite.

Drupe with a bilocular, 2-seeded stone.--Aucuba, diœcious; unilocular ovary; 1 ovule; 1-seeded berry.--Garrya.--Helwingia.

80 species; N. Temp. The fruits of Cornus mas are edible; the wood is very hard; gum is found in some. Several species of Cornus and Aucuba japonica (Japan) are cultivated as ornamental shrubs.

Order 2. =Araliaceæ (Ivies).= Principally trees or shrubs with solid stems. The leaves are scattered, simple or compound, with a sheath more or less developed. The flowers are most frequently situated in umbels or capitula which are either borne singly or in racemes, or in paniculate inflorescences. The small, most frequently yellowish-green flowers are =5=-merous, in the calyx, corolla, and andrœcium; the gynœceum may be 5-merous or may have some other number (=2=-∞). The styles are most frequently several, free; the raphe of the ovules is turned inwards as in the Umbelliferous plants. The fruit is a drupe or berry.--~Stellate hairs often occur. The petals generally have a broad base, and a thick apex which is slightly incurved, and a distinctly valvate æstivation.~

Hedera helix (Ivy) climbs by adventitious roots. The leaves are palminerved and lobed on the sterile branches, but often ovate and not lobed on the flowering branches. ~The flowers are yellowish-green and open in the autumn; they are slightly protandrous, and are visited by flies and wasps. Berries black. Endosperm ruminate.--Panax. Aralia (with Dimorphanthus).~

375 species, 51 genera; especially in the Tropics (E. Asia).--The Ivy, several species of Aralia, e.g. A. japonica (Fatsia), Gastonia palmata, are cultivated as ornamental plants. Paper is manufactured from the pith of Aralia papyrifera (China).

Order 3. =Umbelliferæ.= The stem is herbaceous with hollow internodes; the leaves are scattered, and have a broad, amplexicaul base, a large, most frequently inflated sheath, and generally a pinnate (often very much dissected) blade. ~Entire leaves are found in Hydrocotyle vulgaris; Bupleurum.~

The flowers are ☿, regular, small, but collected in compound umbels, that is, in “simple umbels,” which again are borne in umbels (for exceptions see Hydrocotyleæ); the external flowers in the simple umbel have often subtending bracts, which surround the base as an involucre, and may be termed the small involucre; the internal ones have no bracts; when involucral leaves are present at the base of the compound umbel, they may be termed the large involucre.

The flower has =5= sepals (the median, as usual, posterior), =5= petals, =5= stamens and =2= carpels (in the median line) (Fig. 528). The calyx is often scarcely indicated. The petals have a short claw are most frequently obcordate, or have an incurved apex (Fig. 528 B, C), being incurved in the bud; they are white, rarely yellow (Fennel and Parsnips), blue or red. The flowers are sometimes zygomorphic, especially those on the circumference of the umbel, and in that case it is the petal which is directed outside (anterior) which is the largest, and the two posterior are the smallest (e.g. Heracleum). The stamens are incurved in the bud. The 2 free styles unite at the base into the “stylar-foot” (stylopod), a swollen nectary (Fig. 528 B, C); the ovary is bilocular, the raphe of the ovules being directed inwards. The fruit is a schizocarp, dividing into two mericarps; the plane in which these separate coincides with that of the union of the carpels, and the two nut-like mericarps are in most genera kept together for awhile at the top of a thin, bifid, or undivided stalk (carpophore) which is in direct continuation with the flower-stalk (Fig. 537). Each mericarp has most frequently 5 more or less strongly projecting ridges, the primary ridges (Figs. 530, 532, 534, 535, etc.), of which 3 lie on the back of the mericarp, the dorsal ridges, and 2 on its edge near the plane of division, the marginal ridges; five of these (10 ridges in all in the entire fruit) are placed opposite the calyx-teeth and the others between them. In some genera there are in addition 4 secondary ridges to each mericarp between the primary ones (Fig. 528 E: the secondary ridges bear the long bristles). Inside these secondary ridges, or inside the grooves between the primary ridges, when the secondary ridges are absent, oil ducts (vittæ, schizogenous ducts) are found in the pericarp, most frequently one in each groove; two are also often found on the ventral side of each mericarp (Figs. 528 E, 530 ol, etc.). The seed is most frequently united with the pericarp. The embryo is small and lies high up in the large, most frequently horny endosperm (Fig. 528 D).--The endosperm does not contain starch, but oil, and presents three different forms, of important systematic value: (=a=) those which are quite flat on the ventral side (i.e. the side turned towards the plane of splitting) (Figs. 528 E, 530, 531, 534, etc.): the majority of the genera, ORTHOSPERMEÆ (e.g. Carum, Pastinaca); (=b=) those in which the endosperm on the ventral side is provided with a longitudinal groove, often deep: CAMPYLOSPERMEÆ (e.g. Anthriscus); the transverse section is nearly a crescent (Fig. 532); (=c=) those in which the endosperm is concave on the ventral side (hollow in both longitudinal and transverse sections): CŒLOSPERMEÆ (e.g. Coriandrum) (Fig. 538).

The genera are distinguished first of all by the endosperm and forms of fruit, the ridges and oil-ducts; then by the form of the umbel, the calyx and corolla, by the absence or presence of an involucre, etc.

1. HYDROCOTYLEÆ, PENNY-WORT GROUP. Capitula or simple umbels (all the other groups have compound umbels). No oil-ducts. Orthospermous.--Hydrocotyle (Penny-wort). The fruit is considerably compressed laterally (Fig. 529). The calyx-teeth are small. The leaves are peltate.--Didiscus.--Sanicula (Sannicle). The umbels are small, capitate, generally collected in a raceme; calyx-teeth distinct. ♂-and ♀-flowers in the same umbel. The fruits are round, studded with hooked bristles. No carpophore.--Astrantia has an umbel surrounded by a large, often coloured involucre, with this exception it is the same as the preceding, but the fruit is slightly compressed, with 5 equal ridges. Hacquetia (Dondia).--Eryngium (Sea Holly): leaves often thorny. The flowers are all sessile, the inflorescence is thus a capitulum; each flower is often subtended by a bract, which is thorny like the involucre, resembling the burrs of the Teasel. The sepals are large.--~Lagœcia: one of the loculi of the ovary is suppressed.~

=2.= AMMIEÆ, CARAWAY GROUP (Figs. 530–532). The fruit has only the 10 primary ridges; it is usually short, almost spherical or broadly ovate and distinctly compressed laterally. Oil-canals are most frequently present. Orthospermous (except Conium).--Cicuta (Cow-bane). Pointed calyx-teeth. Glabrous herbs with pinnate or bipinnate leaves. ~C. virosa has a thick, vertical rhizome, divided by transverse septa into many compartments; the leaflets are narrow, lanceolate, and dentate; the large involucre is wanting.~--Apium (Celery). No calyx-teeth. A. graveolens, a maritime plant, has neither large nor small involucre; the umbels are short-stalked or sessile.--Carum (Caraway). Calyx-teeth small; the large involucre is wanting or is only few-leaved. C. carvi (Caraway). C. petroselinum, (Parsley) (Fig. 530). Falcaria; Ammi; Helosciadium; Bupleurum (Hare’s-ear) with simple leaves and yellow corolla; Pimpinella (Fig. 531); Sium; Ægopodium (A. podagraria, Gout-weed) has bi- or tri-ternate leaves, with ovate, dentate leaflets; the large involucre is wanting.--Conium is campylospermous (Fig. 532); the short, broadly ovate fruit has distinctly projecting, often wavy crenulate ridges. C. maculatum (Hemlock) has a round, smooth stem with purplish spots.

=3.= SCANDICEÆ. This group has a distinctly oblong or linear fruit which is slightly compressed laterally, and generally prolonged upwards into a “beak”; wings absent. Campylospermous. Otherwise as in the Ammieæ.--Anthriscus (Beaked Parsley) has a lanceolate fruit, round on the dorsal side, without ridges, but with a ten-ridged beak.--Scandix (Shepherd’s-needle).--Chærophyllum (Chervil): fruit lanceolate or linear with low, blunt ridges; beak absent or very short. C. temulum has a red-spotted, hairy stem.--Myrrhis (Cicely) has a short beak and sharp, almost winged ridges. M. odorata (Sweet Cicely) has very long fruits.

=4.= SESELINEÆ, FENNEL GROUP (Figs. 533, 534). The fruit is slightly elliptical or oblong, in transverse section circular or nearly so, without grooves in the dividing plane; only primary ridges are present. Orthospermous.--Fœniculum (Fennel) has yellow petals; both involucres are wanting; the fruit is oblong. The ridges are thick, all equally developed, or the lateral ridges are slightly larger (Fig. 534).--Æthusa (A. cynapium, Fool’s Parsley); the large involucre is wanting or is reduced to one leaf, the small involucre is composed of three linear leaves which hang downwards on the outer side of the umbels. The fruit is spherical-ovate, with thick, sharp, keeled ridges, the lateral ones of which are the broadest.--Œnanthe (Dropwort); the fruit (Fig. 533) has usually an ovate, lanceolate form, with distinct, pointed sepals and long, erect styles; the ridges are very blunt, the marginal ones a trifle broader than the others.--Seseli, Libanotis, Cnidium, Silex, Silaus, Meum, etc.

=5.= PEUCEDANEÆ, PARSNIP GROUP (Figs. 535–537). The fruit is most frequently very strongly compressed dorsally, with broad, mostly winged, lateral ridges. Only primary ridges. The dorsal ridges may project considerably, but are not winged. Orthospermous.

=a.= The winged lateral ridges stand out from each other, so that the fruit appears to be 4-winged (Fig. 535).--Angelica; Archangelica (Fig. 535); Levisticum (Lovage).

=b.= The winged lateral ridges lie close together, and form one wing on each side of the fruit (Fig. 536).--Pastinaca (Parsnip). Corolla yellow. The dorsal ridges are very weak; the oil-ducts do not reach quite as far as the base of the fruit. Both large and small involucres are wanting; leaflets ovate. Anethum (Dill) is a Parsnip with more distinct dorsal ridges and filamentous leaflets. Peucedanum (Hog’s-fennel); Ferula (with Scorodosma, Fig. 536, and Narthex); Dorema.--Heracleum (Cow-parsnip); the flowers in the margin of the umbels are often very large, zygomorphic, and project like rays, e.g. in H. sibiricum. The fruit is very flat, with very small dorsal ridges; the oil-ducts are more or less club-like and do not reach as far as the base of the fruit (Fig. 537). Imperatoria; Tordylium.

=6.= DAUCEÆ, CARROT GROUP (Fig. 528). The fruit has 18 ridges, i.e. each fruitlet has 5 primary and 4 secondary ridges, the latter being often more prominent and projecting further than the primary ones. The oil-ducts are situated under the secondary ridges (Fig. 528).

=a.= ORTHOSPERMOUS: Daucus (Carrot). The secondary ridges project much further than the primary, and bear on their crests a series of hooked spines (Fig. 528 D, E); these are much longer than the small bristles on the primary ridges. ~The involucral leaves of D. carota (Carrot) are numerous and deeply pinnate; the inflorescence contracts during the ripening of the fruit, and since the external umbels have longer stalks than the central ones, they arch over them, and the inflorescence becomes hollow. For the terminal flower, see below.~--Cuminum; Laserpitium; Melanoselinum.

=b.= CAMPYLOSPERMOUS: Torilis (Hedge Parsley). The primary ridges are covered with bristles; the secondary ridges are not. very distinct on account of the spines, which entirely fill up the grooves. Caucalis (Bur Parsley).

=c.= CŒLOSPERMOUS: Coriandrum (Coriander) has a smooth, spherical fruit (Fig. 538) with a distinct, 5-dentate calyx, the two anterior (i.e. turned outward) teeth being generally longer than the others; the two fruitlets scarcely separate from each other naturally; all the ridges project only very slightly, the curved primary ones least, the secondary ridges most.

POLLINATION. The flowers are adapted for insect-pollination; they secrete nectar at the base of the styles; individually they are rather small and insignificant, but yet are rendered conspicuous by being always crowded in many-flowered inflorescences. Protandry is common, sometimes to such an extent that the stamens have already fallen off before the styles begin to develop (Fig 539, 2). Insect visits are more frequent and numerous as the inflorescences are more conspicuous. The flowers as a rule are ☿, but ♂-flowers are often found interspersed among the others (Fig. 539), and the number of these becomes greater on the umbels developed at the latest period. A terminal flower, which differs from the others in form, and in Daucus carota often in colour also (purple), is sometimes found in the umbel. The nectar lies so exposed and flat that the flowers are principally visited by insects with short probosces, especially Diptera; bees are less frequent visitors, and butterflies rare.--1400 species (175 genera); especially from temperate climates in Europe, Asia, N. Am. About 68 species in this country.

USES. A few are cultivated as ornamental plants. They are, however, useful in medicine,[38] and for culinary purposes on account of the essential oils and gum-resins which in many are formed in root, stem, and fruit. The FRUITS of the following are used: Carum carvi [+] (Caraway), Carum petroselinum (Parsley; also the leaves and root; its home is the Eastern Mediterranean); Fœniculum capillaceum [+] (Fennel; S. Europe); Pimpinella anisum [+] (Anise; E. Mediterranean); Coriandrum sativum [+] (Coriander; S. Eur.); Œnanthe phellandrium (Water Dropwort); Cuminum cyminum (Point Caraway; Africa; cultivated in S. Europe); Anethum graveolens (Dill). The LEAVES of the following are used as pot-herbs: Anthriscus cerefolium (Chervil); Myrrhis odorata (Sweet Cicely; Orient.); Conium maculatum [+] (the green portions; Hemlock). Besides Parsley, the ROOTS of the following are used: Carrot, Parsnip, Sium sisarum (Sugar-root; E. Asia); Chærophyllum bulbosum (Chervil-root); Levisticum officinale (foliage-shoots; S. Europe); Imperatoria ostruthium; Apium graveolens (Celery, the root in conjunction with the internodes); Pimpinella saxifraga and magna (Pimpinell); Archangelica (Angelica, the root of A. norvegica was formerly an article of food in Norway). Poisonous alkaloids are found in a few, such as Fool’s Parsley (Æthusa cynapium), Hemlock (Conium maculatum), Cow-bane (Cicuta virosa) and species of Œnanthe.--Gum-resin is extracted from various species: “Galbanum” from Ferula galbaniflua [+] and rubricalis [+] (Persia); Asafœtida from Ferula scorodosma [+] and F. narthex [+]; Ammoniac-gum from Dorema ammoniacum [+], all from Central and S. W. Asia. “Silphium” was an Umbelliferous plant which grew in ancient times in Cyrene, and from which the Romans extracted a valued condiment.

Family 25. =Hysterophyta.=

This family (with the exception of Aristolochiaceæ) includes only parasitic plants. Partly on this ground, and partly because they all have epigynous flowers, they are considered to belong to the youngest type (which is expressed in the name ὕστερος, the one that comes after). It is not certain to which of the preceding families they are most nearly allied. ~Again, it is a matter of doubt whether the Aristolochiaceæ are related to the others; they are by Engler united with Rafflesiaceæ into one family, Aristolochiales.~

Order 1. Aristolochiaceæ. The majority are perennial herbs or twining shrubs, whose stalked, simple, and generally more or less cordate or reniform leaves are borne in 2 rows and are exstipulate. The flowers are hermaphrodite, epigynous, regular or zygomorphic; perianth-leaves united, simple but most frequently petaloid and 3-merous; 6 or 12 (in Thottea as many as 36) stamens with extrorse anthers. The ovary is more or less completely 4–6-locular with ovules attached in the inner angles of the loculi (Fig. 540 kf). The style is short, and has a large, radiating stigma (Fig. 540 n). Fruit a capsule. Seeds rich in endosperm.

Asarum europæum. Each shoot has 2 reniform foliage-leaves, between which the terminal flower is borne (the rhizome becomes a sympodium by development of the bud in the axil of the upper foliage-leaf). The flower is regular and has a bell-shaped perianth with 3 outer valvate, and 3 inner small segments (which may be wanting). =12= (2 × 6) free, extrorse stamens, 6 carpels.--Aristolochia clematitis (Birth-wort) has an erect, unbranched stem, bearing many flowers in the leaf-axils, in a zig-zag row (accessory buds in a unipared scorpioid cyme). The flowers are zygomorphic (Fig. 540), formed by 3 alternating, 6-merous whorls. The perianth has a lower, much-distended part (k), succeeded by a narrow, bent tube (r), which passes over into an oblique, almost tongue-like projection (6 vascular bundles indicate that the number 6 is prevalent here, as in Asarum); =6= stamens (Fig. 540 a), with the dorsal portion turned upwards, are united with the short style to form a stylar column; they are placed quite beneath the 6 commissural stigmatic rays, which arch over them as short, thick lobes. ~Protogynous; POLLINATION is effected in Arist. clematitis by small flies; these enter the erect unfertilised flower through the tube (Fig. 540 A, l) without being prevented by the stiff, downwardly-turned hairs which line the tube and prevent their escape; they find the stigma (n) fully developed, and may pollinate it with the pollen they have brought with them. The stigmas then straighten and wither (B, n), the anthers open, and the flies may again be covered with pollen; but the hairs which blocked up the tube do not wither until the anthers have shed their pollen, and only then allow the imprisoned flies to escape and effect cross-pollination. Prior to pollination, the flowers stand erect, but after this has taken place they become pendulous, and the perianth soon withers.--A. sipho (Pipe-flower), another species, is a climber, and often grown in gardens; it has only one row of accessory buds in the leaf-axils.--200 species; chiefly in S. Am. OFFICINAL: the rhizome of Aristolochia serpentaria (N. Am.).~

Order 2. =Santalaceæ.= Parasites containing chlorophyll, which, by the help of peculiar organs of suction (haustoria) on their roots, live principally on the roots of other plants. Some are herbs, others under-shrubs. The regular, most frequently ☿-flowers have a simple perianth, which is gamophyllous, 3- or 5 partite with the segments valvate in the bud, and a corresponding number of stamens opposite the perianth-leaves. In the inferior ovary there is a free, centrally placed, often long and curved placenta with three ovules (one opposite each carpel); these are naked, or in any case have an extremely insignificant integument. Fruit a nut or drupe. Seed without testa. Endosperm fleshy. 225 species; chiefly in the Tropics.--Thesium, a native, is a herb with scattered, linear leaves and small 5-merous flowers (P5, A5, G3) in erect racemes; the subtending bracts are displaced on the flower-stalks. Fruit a nut.--Osyris (diœcious shrub; 3-merous flowers) is another European genus.--Santalum album, which grows in E. Ind., yields the valuable, scented Sandalwood, the oil of which is used medicinally.--Quinchamalium.

Myzodendron is a reduced form of the Santalaceæ; the ♂-flowers are without perianth; the perianth of the ♀-flower is 3-merous. About 7 species; S. Am.; parasitic on a Beech (Nothofagus). The fruit has 3 feathery brushes, alternating with the lobes of the stigma, which serve as flying organs and to attach the fruits to a branch (Fig. 541), the brushes twining round as soon as they come in contact with it. There is only 1 seed in the fruit, which germinates by a long, negatively heliotropic hypocotyl, and is attached by a radicle modified into an haustorium.

Order 3. =Loranthaceæ= (=Mistletoes=). Plants containing chlorophyll which are parasites on trees, and most frequently have opposite, simple, entire leaves and regular, epigynous, often unisexual, 2- or 3-merous flowers, with single or double perianth. Stamens equal in number and opposite to the perianth-leaves, free, or in varying degrees united to one another. The inferior ovary is constructed as in the Santalaceæ, the ovules being situated on a low, free, centrally-placed placenta, but the placenta and ovules unite with the wall of the ovary into one connected, parenchymatous mass, in which the embryo-sacs are imbedded. Only 1 (less frequently 2–3) of the 1–6 embryo-sacs is fertile. The number of the carpels however varies. The fruit is a 1-seeded berry, whose inner layer is changed into a tough slimy mass (bird-lime), which serves to attach the fruits to other plants.

The two groups, Loranthoideæ and Viscoideæ, are distinguished by the fact that the former has a distinct “calyculus,” i.e. an entire or lobed, or dentate swelling on the receptacle below the perianth. The majority of the Loranthoideæ have a petaloid perianth; in all the Viscoideæ, on the other hand, it is sepaloid.

The Mistletoe (Viscum album, Fig. 542) is a native, evergreen plant which may be found growing on almost any of our trees (sometimes on the Oak), and, like other Loranthaceæ, it produces swellings of the affected branches. ~Its spherical white berries (Fig. 542 A) enclose (1–) 2–3 green embryos; they are eaten by birds (especially Thrushes), and are partly sown with their excrement, partly struck or brushed off the branches of the trees, the seed being enclosed, at maturity, by viscin, i.e. “bird-lime.” The seeds may also germinate on the branches, without having first passed through the alimentary canal of the birds. On germination, the hypocotyl-axis first appears, as in Fig. 541, and bends towards the branch; the apex of the root then broadens, and forms at the end a disc-like haustorium, from the centre of which a root-like body grows through the bark into the wood, and ramifies between the bark and wood. Suckers are developed on the root like strands which are formed in this manner, without, however, having a rootcap; they are green, and penetrate the wood by the medullary rays (Fig. 542 C). Adventitious buds may also be developed from the root-like strands which break through the bark and emerge as young plants. The young stem quickly ceases its longitudinal growth, and lateral shoots are developed from the axils of its foliage-leaves. These and all following shoots have a similar structure; each of them bears a pair of scale-leaves (Fig. 542 A, a) and a pair of foliage-leaves (Fig. 542 A, b), and then terminates its growth, if it does not produce an inflorescence; new lateral shoots proceed from the axils of the foliage-leaves, and the branching, in consequence, is extremely regular and falsely dichotomous. Only one internode (shoot-generation) is formed each year, so that each fork indicates one year. The foliage-leaves fall off in the second year. The inflorescence is a 3(-5)-flowered dichasium (Fig. 542 A, m is the central flower, n the lateral). The plants are diœcious; the ♂-flower as a rule is 2-merous: perianth 2 + 2, each leaf of which bears on its inner side 6–20 pollen-sacs, each of which opens by a pore; this relationship may be considered to have arisen from the union of the perianth-leaves with the multilocular stamens (2 + 2) placed opposite them. The ♀-flowers always have Pr 2 + 2, G2.--Loranthus is also found in Europe (it has a 3-merous flower), especially in the central and south-eastern districts, on Quercus cerris and Q. pubescens; but the great majority of the 520 species grow in the Tropics on trees which they ornament with their often brightly-coloured flowers, and ultimately kill when present in too great numbers. The pollination in the numerous Loranthaceæ with unisexual flowers, is effected by the wind. In Viscum album this takes place in autumn, the actual fertilisation in the following spring, and the maturity in November or December; in the succeeding month of May the berry is ready to germinate, and falls off.~

USES. Birdlime from Viscum album.

Order 4. =Rafflesiaceæ= and Order 5. =Balanophoraceæ=. These orders comprise root-parasites, almost entirely devoid of chlorophyll; they are reddish or yellow, without foliage-leaves (Fig. 543). As far as our knowledge of these rare tropical plants extends, they have thalloid organs of vegetation resembling the root-like strands of Viscum, or they are filamentous and branched like Fungus-hyphæ; they live in and on the tissues of the host-plant, from which their flowering-shoots, often of mushroom-like form, are subsequently developed (Fig. 543). In order to unfold they must often break through the tissues of the host-plant.

Of the RAFFLESIACEÆ, Cytinus hypocistus is found in S. Europe living on roots of Cistus-plants and to some extent resembling Monotropa (Fig. 543). Rafflesia is the best known; it lives on roots of Cissus-species (belonging to the Ampelidaceæ) in Java; its yellowish-red, stinking flowers attain a gigantic size (one metre or more in diameter), and are borne almost directly on the roots of the host-plant. Besides these there are other genera: Brugmansia, Pilostyles, Hydnora.--To BALANOPHORACEÆ (Fig. 543) belong: Balanophora, Langsdorffia, Scybalium, Sarcophyte, Helosis, etc., and in S. Europe, Cynomorium coccineum.

Sub-Class 2. =Sympetalæ.=

The characters which separate this from the first Sub-class, the Choripetalæ, have been described on page 336. They consist in the following: the flower is always verticillate, generally with =5= sepals, =5= petals, =5= stamens, and =2= carpels (in the median plane), the calyx is generally persistent and gamosepalous, the corolla is gamopetalous and united to the stamens, which are therefore adnate to it, the ovules have only one thick integument and a small nucellus. (The exceptions are noted later.)

This Sub-class is no doubt more recent than the Choripetalæ; it is also peculiar in including fewer trees and shrubby forms than the latter.

The Sympetalæ may be separated into 2 sections:--

=A.= PENTACYCLICÆ (FIVE-WHORLED). The flowers in this section have 5 whorls equal in number, namely, 2 staminal whorls in addition to the calyx, corolla, and carpels; in some instances, one of the staminal whorls is rudimentary or entirely suppressed, but in this case it is frequently the sepal-stamens which are suppressed, and the whorl which is present stands opposite the petals. The flowers are regular. The number of carpels equals that of the sepals, but in one of the orders (Bicornes) they are opposite the petals (the flower being obdiplostemonous); in the other two orders (Primulinæ and Diospyrinæ) they are placed opposite the sepals (the flower being diplostemonous). This section is the most closely allied to the Choripetalæ, since the petals may sometimes be found entirely free, and the stamens inserted directly on the receptacle (Ericaceæ); ovules with two integuments are also found. ~It is very doubtful, whether the orders included under this head have any relationship with the other Sympetalæ. They appear in any case to represent older types.~

=B.= TETRACYCLICÆ (FOUR-WHORLED). The flowers have only 4 whorls, namely, beside sepals, petals, and carpels, only one whorl of stamens, which alternates with the petals; there is no trace of the second staminal whorl, and when the number of carpels is the same as that of the preceding whorls (“isomerous”) they alternate with the stamens; but in most cases there are 2 carpels placed in the median plane (see the diagrams, e.g. Figs. 559, 567, 583, 590, etc.). This section is the largest, and the one which shows the characteristics of the Sympetalæ best. Very irregular flowers are met with.

The following families belong to the =Pentacyclicæ=: 26, Bicornes; 27, Diospyrinæ; 28, Primulinæ.

The remaining families belonging to the =Tetracyclicæ= are:--

=a.= HYPOGYNOUS flowers (with a few exceptions): 29, Tubifloræ; 30, Personatæ; 31, Nuculiferæ; 32, Contortæ.

=b.= EPIGYNOUS flowers: 33, Rubiales; 34, Dipsacales; 35, Campanulinæ; 36, Aggregatæ. The ovaries and ovules in the last family are always reduced to one; and at the same time the fruits become nuts, and the flowers are united into crowded inflorescences.

A. Pentacyclicæ.

Family 26. =Bicornes.=

This family is chiefly composed of shrubs, less frequently of small trees, or perennial herbs; their leaves are undivided, most frequently evergreen, stiff and leathery, and always without stipules. The flowers are ☿ and regular, rarely slightly zygomorphic, most frequently obdiplostemonous, and 4- or 5-merous through all the 5 whorls. The stamens are attached to the receptacle, and as a rule are quite free from the petals, an attachment which is very rare among the Gamopetalæ. They have a simple gynœceum with one undivided style, a commissural stigma, and a multilocular ovary, whose axile placentæ project considerably into the loculi, and bear a large number of ovules. ~The placentæ are sometimes not united, and in consequence, the ovary is 1-locular with incomplete partition-walls, e.g. Pyrola, Monotropa.~ Embryo straight, with endosperm. The carpels are placed opposite the petals.

The diagram is generally Sn, Pn, An + n, Gn, in which n is 4 or 5. To this may be added, that the corolla is in most cases gamopetalous, but in some (especially Pyrolaceæ) perfectly polypetalous; and that the anthers usually open by pores, and often have two horn-like appendages (hence the name “Bicornes”) (Figs. 545, 546); frequently the two halves of the anther are also widely separated from each other at the upper end, so that the pores are placed each one at the end of its own tube (Fig. 546); the pollen-grains in the majority are united into tetrads (Fig. 542 D).--The flowers, as a rule, are pendulous and borne in racemes, coloured (red or white), but odourless. When the fruit is a capsule, the placenta with the seeds attached persists as a central column. A mycorhiza occurs on many.

The majority of plants belonging to this family inhabit cold and temperate countries, or high mountains in tropical regions; they prefer cold and dry or damp places (bogs, heaths, etc.). Plentiful in N. America.

Order 1. =Pyrolaceæ.= Perennial herbs; petals most frequently quite free from each other, and falling off singly after flowering; the anthers are without appendages, and open by pores (Fig. 544), or by a transverse slit. The placentæ are thick. The seeds in the capsule-like fruit (loculicidal dehiscence) are exceedingly small and light, they have a sac-like testa which loosely envelops them, an oily endosperm, and an extremely simple embryo, which consists only of an ellipsoidal, cellular mass, without cotyledons or differentiation into plumule and radicle.

Pyrola (Winter-green) is green, and has also large evergreen foliage-leaves. The flowers, 5-merous, are most frequently borne in racemes without a terminal flower; the anthers are extrorse in the bud with the pores in the lower portion (Fig. 544 A), but they become inverted at a later period, so that the pores open at the top (Fig. 544 C). ~P. uniflora has a single, terminal flower; it winters by its roots, producing from these in the spring aerial, quite unbranched shoots. Chimaphila umbellata.~

Monotropa (Yellow Bird’s-nest) is very pale yellow, without chlorophyll, succulent, and has only scale-like leaves closely pressed upon the stem; it is a saprophyte. The raceme has a terminal flower, and is pendulous before flowering. The anthers open by a semicircular, transverse cleft. ~M. hypopitys reproduces chiefly by root-shoots.~

About 30 species, especially N. Europe, N. America, and N. Asia.

Order 2. =Ericaceæ.= The flower (Fig. 545) is hypogynous, the median sepal posterior; corolla, gamopetalous; the stamens are generally 2-horned, and the fruit is a capsule, less frequently a berry or drupe. At the base of the ovary is a nectar-secreting disc (Fig. 545 B). This order comprises shrubs or undershrubs (rarely small trees), which are evergreen, and as a rule have densely crowded leaves.

=1.= ERICEÆ, HEATH GROUP. Flowers most frequently 4-merous (S4, P4, A4 + 4, G4, united in a 4-locular gynœceum), rarely 5-merous. The withered corolla persists after flowering. The leaves are most frequently acicular, opposite or verticillate; the buds are without scales. The fruit is a capsule.--Calluna (C. vulgaris, Ling) has a deeply 4-cleft corolla, which is less than the coloured calyx; capsule with septicidal dehiscence.--Erica (about 420 species; E. tetralix, Cross-leaved Heath) has a tubular or bell-shaped, 4-dentate corolla, which is much longer than the calyx. Capsule with loculicidal dehiscence.--Pentapera.

=2.= ANDROMEDEÆ. The flowers are 5-merous (S5, P5, A5 + 5, G5), with deciduous corolla. Capsule with loculicidal dehiscence. The leaves are scattered, and incline more to the ordinary broad-leaved forms.--Andromeda; Gaultheria; Cassandra (Lyonia); Cassiope.

=3.= ARBUTEÆ. The flowers as in the preceding group (Fig. 545), but the fruit is a berry or drupe. Arctostaphylos (A. uva-ursi, Bear-berry) has a drupe with 5 stones in a dry, farinaceous pulp; in other species there is 1 stone with several loculi. Arbutus (A. unedo, Strawberry-tree) has a spherical berry.

Pollination is effected by means of insects, especially by bees. The pollen is light and dry, and is shaken out through the pores of the anthers when the insects agitate the horn-like appendages during their visits. Self-pollination takes place, no doubt, in many cases.--800 species; the very large genus, Erica, especially in S. Africa (the Cape).--OFFICINAL: the leaves of Arctostaphylos uva ursi. Arbutus unedo (S. Europe) has an edible, peculiarly warted (strawberry-like) fruit. Many Erica-species are cultivated as ornamental plants.

Order 3. =Rhodoraceæ= (=Rhododendrons=). This differs from the preceding order in the median sepal being anterior, and hence the position of the other floral whorls is also reversed. The flower is hypogynous, in most cases 5-merous; the corolla is most frequently deeply cleft or polypetalous, and falls off after flowering; the anthers open by pores, and have no horn-like appendages. Capsule with septicidal dehiscence.--The shrubs or small trees belonging to this order have, like the Vaccineæ, ordinary foliage-leaves, and the buds are generally provided with large bud-scales.

Rhododendron has 10 stamens, and a slightly zygomorphic flower with deeply 5-cleft corolla (the section Azalea has frequently only 5 stamens, the petal-stamens being absent). They are Alpine plants (200 species) in the mountains of Asia, especially the Himalayas; some in S. Europe.--Menziesia.--Ledum; small, rusty-brown, hairy shrubs with polypetalous, expanded, star-like corolla.--Kalmia (N. Am.) has a cupular corolla, with 10 small, pocket-like depressions in which the anthers are concealed until the arched, elastic filaments are freed from this position by means of the insects, when they quickly straighten themselves in the centre of the flower.--Phyllodoce; Loiseleuria (5 stamens); (Clethra (?); also placed among the Ternstrœmiaceæ).

About 270 species. Several species are ornamental plants. Several plants of the order are more or less narcotic. Ledum palustre has been used as a substitute for hops.

Order 4. =Diapensiaceæ.= Hypogynous flower. 3 floral-leaves beneath the flower (S5, P5, A5 + 0, G3). Stamens on the throat of the corolla. Pollen-grains single. Disc absent. Capsule loculicidal.--9 species from the Arctic regions. It is doubtful whether this order should be included in the Bicornes; perhaps it would be more correctly assigned to the Polemoniaceæ.

Order 5. =Epacridaceæ.= This order comprises those species of the family which are confined to Australia and the South Sea Islands. They are shrub-like plants, resembling the Ericaceæ in habit, in the inflorescence, and in the structure, form, and colour of the flower. They differ especially in having only 1 whorl of stamens (placed opposite the sepals) and in the anthers having only 2 loculi, and opening by a longitudinal slit. Fruit most frequently a drupe (or loculicidal capsule). Epacris-and Styphelia-species are ornamental plants. About 325 species.

Order 6. =Vacciniaceæ= (=Bilberries=). The flower (Fig. 546) is epigynous, the corolla gamopetalous, and the fruit a berry. The latter is most frequently spherical, and bears on its apex the calyx, which is generally very low, almost entire, and with a disc-like expansion inside. The flower is 4- or 5-merous (Fig. 546 B, D). The anthers have 2 pores, and are most frequently 2-horned (Fig. 546 F, G). Small shrubs; the leaves are scattered, not needle-like.

Vaccinium (Bilberry, Whortleberry) has an urceolate, gamopetalous, only slightly dentate corolla, and horn-like appendages to the anthers (Fig. 546). ~V. vitis idæa (Cowberry) is evergreen, with flowers in racemes, and bright red berries; V. myrtillus (Bilberry) and V. uliginosum (Bog Whortleberry) both have black berries with a blue bloom, leaves deciduous.~--Oxycoccus has a polypetalous corolla with the petals projecting backwards. Anthers without appendages. ~O. palustris (Cranberry) has a slender, creeping stem, and is evergreen. Dark red berry.~

Pollination essentially the same as the preceding order.--320 species; especially in N. Am. Some are useful on account of their edible fruits, especially Vaccinium myrtillus and V. vitis-idæa, and in a less degree Oxycoccus, etc. The fruits of V. myrtillus are officinal.

Family 27. =Diospyrinæ.=

The flowers are regular, gamopetalous, typically diplostemonous, with the same number throughout all 5 whorls, thus: Sn, Pn, An + n, Gn, where n most frequently =5 (4–6), rarely 3, 7 or 8. Of the two whorls of stamens the one opposite the sepals is often present only as rudiments or is entirely suppressed, and the completely developed stamens are thus placed opposite the petals. The carpels are generally placed opposite the sepals. The ovary is multilocular with the ovules attached in the inner angles. The fruit is most frequently a berry. The seeds are large, generally solitary, or a few in each loculus.--All plants belonging to this family are trees or shrubs with scattered, single, most frequently entire, penninerved and leathery leaves without stipules; the majority are tropical (America, Asia), some are found in N. Am. and the Mediterranean.

Order 1. =Sapotaceæ.= Plants with latex; anthers extrorse, 1 erect ovule in each loculus; fruit a berry; the seeds with bony, shiny brown testa have a large, lateral hilum. The leaves are frequently covered with silky hairs.--A useful order in several respects (400 tropical species). The wood of some genera, such as Sideroxylon (Iron wood) and Bumelia, is as hard as iron. The latex of Palaquium (P. oblongifolium, P. gutta, and other species), Mimusops and Payena (Sumatra, E. Ind.), is the raw material of gutta percha. The following have very delicious fruits: Lucuma mammosa, Achras sapota, Chrysophyllum cainito (Star-apple), etc. The seeds of Bassia (E. Ind.) contain a large quantity of a fatty oil. Isonandra, Mimusops schimperi are often found in the Egyptian royal tombs.

Order 2. =Ebenaceæ.= Plants without latex, often diœcious; flowers with a more or less leathery perianth. The number of stamens is sometimes increased (by splitting?); ovules 1–2, pendulous in each loculus. Fruit a berry.--250 species; chiefly tropical. Some are well known on account of their hard and black-coloured heart-wood, e.g. Maba ebenus (the Moluccas) and Diospyros ebenum (Ebony-wood, from Tropical Asia) and others.--The fruits are edible e.g. of Diospyros lotus (Date-plum, Asia), which is also cultivated as an ornamental shrub, together with several other species.

Order 3. =Styracaceæ.= The flower is more or less epigynous, and the corolla is almost polypetalous. The stamens (by splitting?) are more than double the number of the petals, and often united at the base. Stellate hairs are frequent.--235 species; Tropical Asia and America, a few for example in the East.--OFFICINAL: Gum-benzoin from Styrax benzoin and perhaps other species (Sumatra and Siam). Halesia tetraptera (N. Am.) is an ornamental shrub with 4-winged fruits.

Family 28. =Primulinæ.=

The flowers are regular, ☿, hypogynous, and gamopetalous. The stamens are equal in number to the petals (Fig. 547) and are placed opposite to them. The ovary is unilocular, with a free, central placenta with 1–many ovules.--The flower is a further development of the Diospyrinæ; the suppression of the calyx-stamens, which commenced in this family, is carried further in the Primulinæ, so that in the majority of cases no trace of them is present, but in certain species and genera (Samolus, Lysimachia thyrsiflora, Soldanella, certain Myrsineæ) some small bodies (scales, teeth, etc.) are found in the position of the suppressed stamens. Again, the lateral portions of the carpels are suppressed, so that the ventral placentæ with the ovules are separated from the dorsal portions, and are united into a free central placenta; this theory is supported by the branching of the vascular bundles, the development, and various comparative considerations.--Sn, Pn, A0 + n, Gn; where n = 4–8, generally 5. The carpels are placed opposite the sepals (Fig. 547).

Order 1. =Primulaceæ= (=Primroses=). This order has many ovules attached to a thick, free, central placenta (Fig. 547); style undivided with a capitate stigma; ovules semi-anatropous; fruit a capsule with many seeds.

All the plants belonging to this order are herbs; stipules wanting; the flower is most frequently 5-merous (S5, P5, A0 + 5, G5; except Centunculus and Trientalis). The corolla and capsule have various forms, but the capsule generally opens by teeth at the apex. The ovules are semi-anatropous (in Hottonia they are anatropous), and the seeds are therefore peltate, with the hilum situated in the centre of one side. The endosperm is fleshy or horny. The flowers are borne either in racemes or in umbels; as bracteoles are typically absent (Fig. 547), cymose branching does not occur.

Primula (Primrose) has most frequently a vertical rhizome, bearing a rosette of leaves at its summit, and long-stalked umbels; corolla rotate or slightly funnel-shaped; the capsule opens at the apex by 5 teeth. The flowers in some species are heterostyled (long-styled or short-styled; Fig. 548). Closely allied are Androsace (with ovate, cup-shaped corolla-tube and ligular scales, alternating with the corolla-lobes) and Soldanella (funnel-shaped corolla with laciniate lobes and most frequently ligular scales).--Hottonia (Water-Violet) is an aquatic plant with pectinate leaves and heterostyled flowers.--Cortusa. Dodecatheon. Cyclamen (Fig. 549) has solitary, long-stalked flowers, and a rotate corolla with the lobes reflexed; the stalk of the capsule rolls up spirally; the tuberous rhizome is formed by the hypocotyledonary internode. Only 1 cotyledon.--Lysimachia (Money-wort); stem-internodes well developed, leaves opposite or verticillate, calyx almost polysepalous, corolla deeply 5-partite (Fig. 550). The flowers are solitary or in racemes.--Anagallis (Pimpernel), leaves opposite, flowers solitary; the fruit a pyxidium (Fig. 551); similarly in Centunculus, which is 4-merous.--Trientalis, the flowers are most frequently 7-merous.--Glaux (Sea Milk-wort) is a creeping maritime plant with opposite leaves; flowers solitary in the leaf-axils, corolla absent, but with coloured calyx. ~The petals are usually developed later than the stamens in the Primulaceæ; but in this instance they are entirely suppressed.~--Samolus (Brookweed) differs from all the others in having an epigynous flower; barren sepal-stamens are also present. The bracts in the racemose inflorescences are displaced along the flower-stalks.

POLLINATION. Insect-pollination in the majority; cross-pollination is promoted in some by heterostyly (Fig. 548).--300 species; especially in northern temperate zones; the majority on mountains (Soldanella, Androsace, etc.); almost absent in the Tropics. A large number are ORNAMENTAL PLANTS, e.g. Primula auricula (from the Alps), P. sinensis (China), P. elatior (Oxslip, a native) and grandiflora, etc. Cyclamen europæum (Alpine Violet); the tubers are poisonous.

Order 2. =Myrsinaceæ.= Trees or shrubs; evergreen, tropical Primulaceæ with fleshy fruits and few seeds, embedded in the placenta. The leaves are nearly always dotted with yellow glands (schizogenous resin-receptacles).--550 species; especially Am.--ORNAMENTAL PLANTS: Ardisia crenulata (W. Ind.); other genera: Clavija, Maesa, Theophrasta (barren sepal-stamens), Myrsine, Jacquinia (barren sepal-stamens), etc.--Ægiceras, allied to this order, comprises arborescent plants, often growing with Rhizophora in tropical forests, along the shore. The embryo germinates while still in the fruit.

Order 3. =Plumbaginaceæ.= This order has a position of the stamens similar to that in Primulaceæ (S5, P5, A0 + 5, G5), but it differs from these in the flower, which has generally a membranous, dry, thin, coloured, folded, almost entire calyx and an almost entirely polypetalous corolla, which, as a rule, has twisted æstivation and is only united with the stamens at its base; but more especially it differs in the ovary, which bears 5 free or almost free styles and only 1 basal ovule with a long, twisted funicle (the placenta of the Primulaceæ is here so much reduced that it bears only 1 ovule). The fruit is a nut or capsule. The radicle is turned outwards. Endosperm mealy.--To this order belong herbs or under-shrubs, which are especially natives of the sea-coast and of salt-steppes; they also resemble the Primulaceæ in the scattered, undivided, entire leaves (without stipules), often in rosettes, and the inflorescence borne on a long stalk. In opposition to the Primulaceæ, the bracteoles are typically present, and hence the branching is generally cymose (scorpioid).

Armeria (Thrift) has a round capitulum, composed of closely-packed dichasia, surrounded at its base by an involucre with peculiar prolongations, directed downwards, and united into a sheath protecting the intercalary zone of growth. The pericarp is finally ruptured at the base, and drops off like a hood.--In Statice (Sea-lavender), the unipared scorpioid cymes are prolonged and collected into panicle-like inflorescences.--~Plumbago is the genus which approaches nearest to the Primulaceæ, and differs most from the characters given above. It has capitate or spike-like inflorescences, a salver-shaped corolla, and the stamens are not attached to the corolla. The style is only divided at the extremity; the calyx is not membranous, but is covered with sticky, glandular hairs.~

250 species; chiefly in the Mediterranean and about the Caspian Sea, on salt-steppes and beaches. Some are Tropical; a few are ornamental plants.

B. Tetracyclicæ.

a. Tetracyclicæ with hypogynous flowers.

Family 29. =Tubifloræ.=

The flower is regular, ☿, and hypogynous. The gamopetalous type is present in this family with great uniformity, without suppression or splitting; S5, P5, A5, G2 (3–5). The stamens are all fertile, alternating with the lobes of the corolla. Gynœceum with 2, more seldom 3–5 syncarpous carpels. Style nearly always simple; 2 dorsal stigmas. In each carpel 2–∞ ovules. At the base of the ovary is found a yellowish ring-like nectary (Fig. 552 C), sometimes 5-sinuate or 5-partite.--The leaves are nearly always scattered; stipules are absent.--~The Solanaceæ, which formerly were classed here, are so closely allied to the Personatæ, that it would be unnatural not to place them first in this family; and the Boraginaceæ (which were also placed in the Tubifloræ) appear to be best united, with the Labiatæ and others, into one family Nuculiferæ.~

Order 1. =Polemoniaceæ.= The flowers are regular; S5, P5, A5, G3. The calyx and corolla have united leaves, the petals twisted to the right in æstivation (all the left edges being covered). The ovary is 3-locular with 2–∞ ovules in each loculus; the style is trifid at the apex; the fruit is a 3-valved capsule. Embryo straight; endosperm fleshy. The inflorescences are dichasia passing over into unipared helicoid cymes (the shoot of the lower bracteole being the more strongly developed).--Herbs without latex. 150 species; especially Western N. Am.--Phlox (salver-shaped corolla; entire, opposite leaves), Polemonium (campanulate or almost rotate corolla; scattered, pinnate leaves), Leptosiphon, Gilia, Collomia, Cobæa (climbing, like the Vetches, by tendrils at the ends of the leaves), etc. They are frequently ornamental plants.

Order 2. =Hydrophyllaceæ.= This order approaches very closely to the Boraginaceæ. Herbs with pinnate or palmate leaves; S5, P5, A5, G2. The lobes of the corolla are imbricate in æstivation. Generally 2 median carpels. The ovary is most frequently unilocular, and the seeds are situated on 2 parietal placentæ; capsule 2-valved; embryo straight; endosperm fleshy. In the corolla-tube, opposite the corolla-lobes, there are frequently appendages of various forms, which resemble those of Cuscuta. The inflorescences correspond exactly with those of the Boraginaceæ, being unipared scorpioid cymes, which, prior to opening, are tightly rolled up.--130 species, especially in N. Am. (California, etc.). Many annual species of Phacelia, Nemophila, Whitlavia, Eutoca, Cosmanthus, etc., are cultivated in gardens as ornamental plants. Hydrolea (has a bilocular ovary, and two free styles).

Order 3. =Convolvulaceæ= (=Bindweeds=). The flower is regular, hypogynous, with 5 almost free sepals (quincuncial æstivation), P5, A5, G2 (rarely 3–5). The corolla is very characteristic; it is (with various forms) almost entire, or slightly 5-lobed, and folded longitudinally in the bud in such a way that 5 projecting, flat portions, tapering towards the top and frequently differing in colour and hairiness from the rest, are visible externally and applied close together, while the remainder of the corolla is folded inwards (Fig. 552 A); and hence the whole corolla is strongly twisted to the right in the bud. The gynœceum most frequently has a bilocular ovary; in each loculus there are only 2 (erect) anatropous ovules on the placenta, which is not especially thickened (Fig. 552 D, E); each loculus is sometimes divided into two by a false septum (a relationship with the Boraginaceæ, etc.); style simple with most frequently a bilobed stigma, or a bipartite style. The fruit is nearly spherical, most frequently a capsule. The seeds are erect, and have a large hilum at the base. The embryo is curved, with leaf-like, thin, bilobed, most frequently folded cotyledons; endosperm absent or mucilaginous.

=1.= CONVOLVULEÆ, BINDWEED GROUP. The majority are twining (to the left) herbs, with latex. The leaves are scattered, without stipules, often long stalked, and nearly always with cordate base; some are palmately lobed. The flowers are most frequently solitary in the leaf-axils, large, quickly withering.--Convolvulus (Fig. 552), Calystegia (unilocular ovary, 2 large bracteoles), Ipomœa, Batatas, Evolvulus (with a doubly bifid style), Calonyction, Pharbitis, etc.

=2.= DICHONDREÆ. This group is a more primitive form, not twining, and without latex. It has 2 free carpels with basal style (as in Boraginaceæ) and valvate corolla.

=3.= CUSCUTEÆ, DODDER GROUP (Fig. 553). Parasites, with round, filamentous stems, bearing only scale-like leaves and almost destitute of chlorophyll (they are reddish or yellowish); they are parasitic upon other plants, around which they twine, first with narrow, compact coils from which haustoria (Fig. 553 A) are developed which enter the host-plant, and then with wider coils by which they raise themselves to other portions of their host or try to reach other plants. On germination a very temporary primary root is developed, which bears root-hairs as far as the tip (rootcap is wanting); it only serves as a kind of reservoir for water, and perishes very soon after the seedling has fastened on to a host. The embryo is filamentous and rolled up spirally (Fig. 553 C), and is sometimes destitute of cotyledons. The flowers are crowded into capitulate inflorescences, complicated by accessory shoots (Fig. 553 A); they have S5, P5 (imbricate æstivation), A5 (and beneath the stamens 5 scales on the corolla-tube), G2. Fruit a capsule opening by a lid.--Cuscuta europœa, C. epilinum (Flax-Dodder), C. epithymum (Lesser-Dodder), C. trifolii (Clover-Dodder), etc., are parasitic on different hosts, or parasitic each on its own particular host.

840 species; the majority in the Tropics, especially Am. Many are ornamental plants. OFFICINAL: some on account of their purgative properties: the tuberous roots of Ipomæa purga (Jalap, from Mexico) and the dried latex (“Scammony”) of Convolvulus scammonia (from the East). The tuberous roots of Batatas edulis (Trop. S. Am.) are used as a common vegetable (Sweet Potato) in the Tropics.

Family 30. =Personatæ.=

The type of the flower is: S5, P5, A5 (of which one, or in some cases several, are suppressed), and G2. The flowers are hypogynous, ☿, perfect with gamopetalous corolla, but most frequently irregular (medianly zygomorphic, except Solanaceæ), the corolla being bilabiate (divided into a posterior part of two lobes and an anterior part of three lobes), and the stamens 4, didynamous (the posterior being suppressed). The ovary has 2 loculi (only 1 in Utriculariaceæ, Gesneriaceæ, Orobanche); the placenta in the first-named orders (1–7) is most frequently very thick, and bears a great many ovules (Figs. 554, 555, 557, 562); the number of ovules in the last orders (8–9) is considerably reduced (Fig. 570).

Special mention may be made of the apparently 4-merous flower which is found, e.g. in Veronica and Plantago (Figs. 567, 562 C, 570, 571), and which arises from the typical 5-merous flower by the suppression of the posterior sepal and the posterior stamen, and by the union of the two posterior petals into one.--Terminal flowers very seldom occur on the main axis, and would not harmonise well with the very irregular form of the flower. When they do occur, they are, as a rule, “peloric,” i.e. regular (in Linaria vulgaris two kinds of peloric flowers occur,--one with 5 spurs, and one without spurs). The halves of the anthers are often divided as far as the base, and laterally so widely separated from each other as to assume an almost straight line (Figs. 563, 564). There is generally a nectary (“disc”) round the base of the ovary, often 5-lobed (or divided into free glands).--A common vegetative characteristic is the absence of stipules.

The 9 orders of the Personatæ are: 1, Solanaceæ; 2, Nolanaceæ; 3, Scrophulariaceæ; 4, Utriculariaceæ; 5, Gesneriaceæ; 6, Bignoniaceæ; 7, Pedaliaceæ; 8, Acanthaceæ; 9, Plantaginaceæ.

Order 1. =Solanaceæ.= The flower (Figs. 554, 555, 559) is hypogynous, regular (zygomorphic in Hyoscyamus), ☿, and gamopetalous, with S5, P5 (most frequently imbricate or valvate), A5, G2, the 2 carpels being placed obliquely (Fig. 554); the bilocular ovary has a very thick axile placenta (Figs. 554, 555 H, 557), which extends almost as far as the wall of the ovary. The fruit is a capsule or berry; the seeds are more or less reniform, and the embryo is curved (rarely straight), in a fleshy endosperm (Figs. 555 F, G; 561).--Both arborescent and herbaceous forms are found in the order; leaves scattered without stipules, but with variously formed laminæ (always penninerved). A peculiar leaf-arrangement is found in many species, viz. the leaves are borne in pairs, a large and a smaller one together; these pairs stand in 2 rows, and the flowers are then situated between the individual leaves in each pair, apparently not in a leaf axil. The inflorescences are frequently unipared scorpioid cymes without floral-leaves.

Zygomorphic flowers occur, and thus form a transition to the closely allied Scrophulariaceæ; the zygomorphy sometimes shows itself only in the relative length of the stamens, sometimes also in the corolla (Hyoscyamus).--Nicandra is 5-merous throughout all the whorls.--The peculiar relative leaf-arrangement in this order occurs from sympodial branching and displacement. The most simple is, e.g. Datura (Fig. 556 A); each shoot-generation in the floral parts of the plant has only 2 foliage-leaves (f^1 and f^2), and then terminates in a flower; the axillary buds of both the foliage-leaves are developed and form a dichasium, but since the leaves are displaced on their axillary-shoots as far, or almost as far, as the first leaf of these axillary-shoots, the flowers are borne singly on the dichasial branches, and all the branches appear to be without subtending leaves (Shoot I is white, II shaded, III white, etc., diagram A). Scopolia and others (Fig. 556 B) differ in that the lowest and smallest (f^1) of the two leaves on each shoot is barren, and is therefore not displaced; but the upper one (the second bracteole, f^2) is displaced as in the first instance, and consequently it assumes a position near the first leaf (the shaded leaf f^2 of shoot I being placed near the white leaf f^1 of shoot II, etc.,) of the next youngest shoot-generation, and hence the leaves are borne in pairs; the flower placed between the two leaves of a pair is therefore the terminal flower of the shoot to which the smaller of the two leaves belongs, and the larger leaf is the subtending leaf for the floral shoot itself.

=A.= FRUIT A CAPSULE. Nicotiana (Tobacco) has a 2-valved capsule with septifragal dehiscence; the valves separate at the apex; the corolla is funnel-shaped, tubular, salver-shaped or campanulate. The flowers in panicles.--Datura (D. stramonium, Thorn-apple) has a (frequently spiny) capsule (Fig. 558), which is falsely 4-locular (at the top, bilocular) and opens septifragally with 4 valves. The lower part of the calyx persists as a thick collar (see Fig. 558). The corolla is funnel-shaped. The flowers are solitary, large.--Hyoscyamus (H. niger, Henbane) has a pyxidium (Fig. 557) enclosed in the campanulate, completely persistent, thick-walled calyx. The flowers are slightly zygomorphic, and borne in unipared scorpioid cymes. ~Scopolia (pyxidium); Fabiana (Heather-like shrub); Petunia (slightly zygomorphic flower; funnel-shaped corolla); Nierembergia; Brunfelsia (almost a drupe); Franciscea; Browallia.~--Among those with capsular fruits are found the most anomalous forms, which by their zygomorphic flowers and often didynamous stamens present the transition to the Scrophulariaceæ: Salpiglossis; Schizanthus (lobed petals; 2 perfect, and 3 rudimentary stamens).

=B.= FRUIT A BERRY. Solanum (Nightshade); rotate corolla (Fig. 559). The stamens have short filaments, the anthers stand erect, close together round the style, like a cone in the centre of the flower, and open by pores at the apex (Fig. 560). ~S. tuberosum (the Potato-plant); the Potato-tuber is a swollen, underground stem; the “eyes” are buds, situated in the axils of its scale-like, quickly-perishing leaves.~--Lycopersicum resembles Solanum in the flower, but the united anthers open by longitudinal clefts and have an apical appendage. The cultivated species, L. esculentum (Tomato), has often a higher number than 5 in the flower, and in the fruit several loculi of unequal size.--Physalis (Winter Cherry); the calyx ultimately swells out in the form of a bladder, becomes coloured, and loosely envelopes the spherical berry.--Capsicum (Guinea Pepper-plant); some species have very large, irregular, rather dry (red, yellow, black) berries, which are unilocular in the upper part.--Lycium (false Tea-plant); the corolla is salver- or funnel-shaped; shrubs; often thorny.--Atropa (A. belladonna, Deadly Nightshade, Fig. 555); corolla campanulate; the calyx projects beneath the spherical, black berry. The flowers are borne singly.--Mandragora; (Mandrake); Nicandra (ovary often 5-locular).--~A small tropical group: CESTREÆ (Cestrum, Habrothamnus, etc.) has an almost straight embryo, which may also be found e.g. in species of Nicotiana. Related to the Scrophulariaceæ.~

About 1,500 species; the majority within the Tropics, outside these limits especially in America. Solanum nigrum is a common weed.--The Potato-plant (Solanum tuberosum), from Peru and Chili, was introduced into Europe in 1584 by Sir Walter Raleigh. (Potatoes = Batatos). The fruits of several serve as condiments: Chilies or Pod-pepper (Capsicum annuum and longum), and the Cayenne-pepper (C. baccatum and others), whose fruits also are officinal, were brought to Europe from S. America by Columbus, and are commonly cultivated in Tropical America; Lycopersicum esculentum (Tomato) and others from Peru; Solanum ovigerum (Egg-plant); Solanum melongena, etc. Poisonous, acrid, narcotic properties (alkaloids, etc., solanine, nicotine, atropine, hyoscyamine) are found in many: Atropa belladonna (from S. Europe; the roots and leaves are officinal); Solanum dulcamara (Bitter-sweet; formerly officinal), S. toxicarium (Guiana); Datura stramonium from Asia (leaves and seeds officinal), D. sanguinea, metel, tatula, and others; Hyoscyamus (officinal: the leaves and seeds of H. niger); Nicotiana tabacum (Virginian tobacco, officinal: the leaves), N. rustica and others from Trop. America (Tobacco was introduced into Europe in 1560); Cestrum-species. Duboisia myoporoides (Australia); the leaves contain hyoscyamine and are used in medicine. A number of species of these genera are ornamental plants.

Order 2. =Nolanaceæ.= These most resemble the Convolvulaceæ in the corolla, but the Solanaceæ in their branching, and leaf-arrangement (in pairs, etc.). The diagram is the same as in Nicandra with 5 carpels, but the fruits of this order most frequently form, by invaginations in various directions, an ovary (with 1 style) consisting of numerous and irregularly grouped, 1-ovuled cells; the fruit is a schizocarp with many 1-seeded fruitlets.--Nolana (Western S. America): a few are ornamental plants.

Order 3. =Scrophulariaceæ.= The flower is hypogynous, ☿, zygomorphic, with the usual type: S5, P5, A5, and G2, the latter placed in the median plane; some genera have all 5 stamens developed (Fig. 562 A), but most frequently the posterior one is suppressed and the flower becomes didynamous (Fig. 562 B). The fruit, as in the capsular-fruited Solanaceæ, is a bilocular, 2-valved capsule, with a thick, axile placenta, and most often septicidal dehiscence (Fig. 563 C). The numerous seeds are not reniform as in many Solanaceæ, and have a straight, or only slightly curved embryo, with abundant endosperm (Fig. 563 D).--The majority are herbs; some are arborescent; the leaves are opposite or scattered, but stipules are wanting as in the whole family.

The Scrophulariaceæ are closely allied to the Solanaceæ, and there is, properly speaking, no characteristic feature which absolutely separates them. The somewhat irregular corolla, with five stamens of unequal length in Verbascum, is also found in Hyoscyamus; curved and straight embryos are found in both orders. The activation of the corolla in the Scrophulariaceæ is simple imbricate, in the Solanaceæ most frequently folded imbricate (in Atropa and those allied to it, imbricate without folding). The genera (about 164) are distinguished according to the form of the corolla, number of stamens, inflorescence, arrangement of the leaves, etc. Verbascum belongs to the most primitive 5-stamened forms, and from it proceed a long series down to Veronica, with only two stamens and most frequently the posterior sepal suppressed.

=1.= ANTIRRHINEÆ, SNAPDRAGON GROUP. This has most frequently a descending æstivation of the petals (the posterior petals are outside the lateral ones, which again enclose the anterior; Fig. 562 A, B). The plants belonging to this group are not parasites.

=a.= =5-stamened.=--Verbascum (Mullein, Fig. 563 A) has a slightly irregular, rotate corolla; five stamens (frequently covered with woolly hairs), of which the two anterior ones are the longer and differ often also in other respects. ~The inflorescences are racemose, often with several series of accessory dichasia in the axil of each primary floral-leaf. The leaves are scattered and, together with the stems, are often covered with a grey felt of branched hairs.~

=b.= =4-stamened, didynamous= (Fig. 564).--Scrophularia (Fig-wort, Fig. 565) has cymose inflorescences in a panicle; the corolla (Fig. 565) is urceolate, short two-lipped; the posterior stamens are present as a scale below the upper lip of the corolla (Fig 565 s). ~S. nodosa has a tuberous rhizome.--Pentstemon; the posterior stamen is barren and very long.~--Antirrhinum (Snapdragon). The corolla (Fig. 564) is personate, i.e. bilabiate, but with the under lip arched to such an extent that it meets the upper lip, closes the corolla throat, and entirely conceals the stamens and style; the corolla-tube is produced into a short pouch at the base on the anterior side. The capsule is oblique and opens by 2–3 pores, formed by small, dentate valves. In Linaria (Toad-flax) the pouch is produced into a spur. Sometimes there are traces of the posterior stamens. The capsule opens by large pores (one for each loculus), produced by large, many-partite valves. L. vulgaris reproduces by suckers.--Digitalis (Foxglove, Fig. 566) has long racemes with drooping flowers; the posterior sepal is small (a step towards complete suppression, as in Veronica); the corolla is obliquely campanulate, and generally nearly 4-lobed, the two posterior petals coalescing.--Alonsoa; Nemesia; Chelone; Herpestis; Mimulus; Torenia; Vandellia; Limosella (L. aquatica, Mud-wort, native); Scoparia; Capraria; Erinus (found on the Roman Camp at Chesters, Northumberland, and supposed to have been introduced from Spain by the Roman soldiers); Celsia (near Verbascum); Maurandia; Lophospermum; Rhodochiton; Collinsia; Nycterinia, etc.

=c.= =2-stamened.=--Gratiola (Water-hyssop). 5-partite calyx. The upper lip of the corolla is undivided or slightly bifid; the two anterior stamens are either entirely absent or are reduced to staminodes (a transition to Veronica).--Veronica (Speedwell), most frequently 4-partite calyx; 4-lobed, rotate, zygomorphic corolla with 2 perfect stamens and no trace of the others (Figs. 567, 562 c); capsule with loculicidal dehiscence. Calceolaria; the corolla has two slipper-like lips.

=2.= RHINANTHEÆ, YELLOW-RATTLE GROUP. Herbs, all of which (with the exception of Lathræa) are annual parasites with green foliage-leaves. They attach themselves by haustoria to the roots of other plants and draw nourishment from them. The majority turn black when dried. Racemose inflorescences. In many the calyx is 4-partite, the posterior sepal being absent, or very small. The corolla is distinctly bilabiate (Fig. 568), with most frequently ascending æstiration; in the majority it does not become detached at the base, but by means of a ring-like cut some distance up the tube; 4 didynamous stamens; pollen-grains dry, easily falling out; the anthers are often furnished at the base with bristles or hairs (Fig. 568) which play a part in the pollination, the probosces of the insects, being forcibly pushed against them, agitate the anthers and shake out the pollen-grains. Capsule with loculicidal dehiscence.--Euphrasia (Eye-bright), Melampyrum (Cow-wheat), Rhinanthus (Yellow-rattle), Odontites (Bartsia), Pedicularis (Louse-wort), and Lathrœa (Tooth-wort) all have native species. The last named is pale yellow, or reddish (without chlorophyll); ~it is a parasite on the roots of the Hazel, Beech and other shrubs, having an aerial stem, and an underground, perennial rhizome, covered with opposite, scale-like, more or less fleshy leaves with a number of internal glandular, labyrinthine cavities. The inflorescence is a unilateral raceme. It approaches Gesneriaceæ in having a unilocular ovary with two parietal placentæ.~

The mechanical contrivances for POLLINATION are so numerous that no general principle can be laid down. Personate flowers, like those of Antirrhinum are only accessible to strong insects, such as humble-bees, which can force themselves between the two lips, and so become dusted with pollen on the back. In Euphrasia and other Rhinantheæ the insects become covered with smooth, powdery pollen when they shake the anther-apparatus in touching the hairs and bristles mentioned above. Scrophularia nodosa is protogynous (Fig. 565). Digitalis purpurea, however, is protandrous. Mimulus luteus and some others have sensitive stigmatic lobes, which shut up on being touched. The Veronica-species constitute a series, from large-flowered down to small-flowered forms, and parallel with them are found various gradations from insect-to self-pollination. In some (as Euphrasia officinalis, Rhinanthus crista galli) there are two kinds of flowers: large, which are pollinated by insects, and small, which are self-pollinated (Fig. 568). Lathræa squamaria (Tooth-wort) is a protogynous spring-flowering plant, largely visited by humble-bees. Others have cleistogamic flowers. Nycterinia capensis opens its flowers at night.

2,000 species; chiefly from the Temp. OFFICINAL: Digitalis purpurea (the leaves; Europe), a poisonous plant. Verbascum thapsus and thapsiforme, Veronica officinalis (“Herba V.”), Gratiola officinalis (“Herba”) have medicinal uses. The whole of the Scrophulariaceæ are more or less suspicious, if not actually poisonous, and none serve as food. Many are ORNAMENTAL PLANTS: Mimulus luteus (N. America), Paulownia imperialis (the only species; in Japan; a tree), Antirrhinum vulgare (S. Eur.), Linaria, Pentstemon, Veronica, Calceolaria (Peru, Chili, etc.).

Order 4. =Utriculariaceæ.= To this order belong only perennial, insectivorous, aquatic, and marsh-plants (200 species) with a more or less characteristic appearance. They differ from the Scrophulariaceæ, especially in having =2= stamens (the anterior) and a unilocular ovary, with free, central placenta (like that of the Primulaceæ). For the rest the flower is distinctly bilabiate, both in the calyx and corolla. Two-valved capsule; no endosperm.

Pinguicula (Butter-wort) has a rosette of leaves close to the ground; these are sticky, covered with glandular hairs, and roll round any small insects which may be caught upon them; flowers solitary, terminal on a long scape; calyx, 5-partite; corolla with spur. The embryo germinates with 1 cotyledon.--Utricularia (Bladder-wort). Our native species are floating, without roots, with hair-like, divided leaves, studded with peculiar bladders (in the Tropics there are terrestrial species, with ordinary foliage). The bladders (Fig. 569) have an aperture, closed by a valve opening inwards, so that small aquatic animals are allowed to enter, but are not able to escape; they are thus entrapped in the bladders, and are probably used as food. Calyx bipartite; corolla personate with spur.

The embryo of Utricularia is very imperfect, scarcely more than a spherical, cellular mass, with a few slight leaf-rudiments. On the germination of U. vulgaris, several bristle-like leaves develop into a compact rosette; the stem then develops, and also the finely-divided, bladder-bearing leaves. A primary root is not developed. The stems branch copiously and in a very peculiar manner. The growing-point of the stem is rolled spirally.--The stigmatic lobes are sensitive and close on being touched; self-pollination often takes place, however, in Pinguicula.

Order 5. =Gesneriaceæ.= The flower in this order may be both epigynous (Gesnerieæ) and hypogynous (Cyrtandreæ), but otherwise is nearly the same as in Scrophulariaceæ, only that the ovary is unilocular, with 2 parietal, often bifid, placentæ. Of the 5 stamens the posterior is rudimentary, or (more rarely) entirely wanting, and the others are didynamous (Cyrtandreæ have often only 2 stamens); their anthers are generally glued into a quadrangular mass. The majority are herbs with juicy stems, opposite, verticillate or scattered leaves without stipules, often, like the stems, thick and juicy, soft-haired or glabrous. The corollas are often highly-coloured (scarlet, red-yellow, etc., and spotted internally), large and magnificent, so that many species are ornamental plants. GESNERIEÆ (often epigynous) have endosperm; S. Am.--CYRTANDREÆ, hypogynous, without endosperm; Asia, S. Africa.--Streptocarpus, neither the primary root nor primary shoot attains development; one of the cotyledons dies, while the other grows and becomes a very large foliage-leaf, from which spring adventitious roots and adventitious inflorescences.

500 species. Gloxinia, Achimenes, Gesneria, Alloplectus, Tydæa, Columnea, Nægelia, Æschynanthus, and others, especially in the forests of tropical America. Some are epiphytes on trees, others prefer the leaf-mould of the forest and crevices of cliffs. Several genera have peculiar, catkin-like, underground shoots, with scale-like compact leaves; others have tubers.

Orobanche (Broom-rape) is allied to this order as a parasitic form. It is a parasite on the roots of other plants, not like Lathræa by means of thin rootbranches with haustoria, but growing with the base of its stem in close contact with its host, and probably even often protruding a kind of thallus into it, in a manner similar to the Loranthaceæ. Its aerial shoots are not entirely destitute of chlorophyll, but are not green; they only bear scale-leaves and terminate in a raceme or spike-like inflorescence.--Some Orobanche-species are detrimental to various cultivated plants (Hemp, Lucerne, Tobacco, etc.). The flowers are strongly zygomorphic; the posterior sepal is often wanting, and the anterior are united to the two lateral ones. Ovary unilocular, as in Gesneraceæ, with 2 or 4 parietal placentæ.--The exceedingly small seeds have a very rudimentary embryo, formed of an ellipsoidal, cellular mass, without indication of cotyledons or other organs.--About 100 species; especially in the Mediterranean region.

Order 6. =Bignoniaceæ.= 500 species; nearly all trees and shrubs, and to a great extent lianes, climbing by tendrils (modified leaves), which are sometimes terminated by a special clasping apparatus. These lianes have, as a rule, an anomalous stem structure, the wood being either divided into four wedges at right angles to each other, separated by four grooves filled with secondary wood-parenchyma, or a greater number of wedges occur, by the cambium ceasing to form wood in several places. The leaves are most frequently opposite and compound; the flowers in the main are similar to the didynamous Scrophulariaceæ, and especially resemble those of Digitalis purpurea; they are bilabiate, large, and beautiful, campanulate or trumpet-shaped, many of the prettiest ornamental plants in the Tropics belonging to this order. The fruit is most frequently a large, woody, 2-valved, siliqua-like, septifragal capsule, whose valves separate from the flat and broad partition-wall, which bears the large, generally winged seeds: Tecoma; Bignonia.--In gardens: Catalpa syringæfolia (Trumpet-wood); Tecoma radicans (from S. Am.).--“Palisander”-wood is from Jacaranda (S. Am.).--Eccremocarpus (N. Am.) forms, by its unilocular capsule, a transition to the Gesneriaceæ (E. scaber; herbaceous).

Crescentia is allied to this order; C. cujete (Calabash) is its best known species. The fruit (unilocular with 2 parietal placentæ) is a very large, spherical or ellipsoidal berry, with a firm, finally woody outer layer. After the removal of the juicy interior, these are commonly used as drinking vessels in Tropical America.

Order 7. =Pedaliaceæ.= Sesamum (orientale and indicum); very important oil-plants, which from olden times have been cultivated in tropical Asia and Africa for food and as medicinal plants, and are now cultivated in America also. The seeds are used as a raw material in the manufacture of soap in Europe.--To this order also belong Martynia and Craniolaria, which have a long horned capsule and sensitive stigmas.--46 species.

Order 8. =Acanthaceæ.= 1,500 species; mostly erect, slender, branched herbs or shrubs, rarely arborescent, especially in S. Am. and Ind. The branches frequently have swollen nodes; the leaves are opposite, penninerved, undivided, more or less lanceolate or elliptical, and generally leave a distinct scar when they fall off. Stipules are wanting. The flowers are solitary or in dichasia, which are arranged in 4-rowed spikes or racemes, each flower with its subtending bract, which may be brightly coloured, and most frequently also with two bracteoles. With regard to the corolla (which is often labiate, in any case irregular, and frequently prettily coloured), the 2 or 4 didynamous stamens (of whose anthers one half is inserted lower than the other, or suppressed) and the gynœceum, the Acanthaceæ are true Personatæ, approaching most nearly to the Scrophulariaceæ: they differ from the other orders especially in the fruit, which is a bilocular, 2-valved, often elastically dehiscing capsule, which never has more than 2 rows, and in some only 2 seeds in each loculus, the seeds being often compressed and borne on strong, curved or hook-like funicles (retinacula) which persist after dehiscence. Embryo curved without endosperm; radicle pointed downwards.--Cleistogamic flowers are found in several species. Cystoliths are common.

The following grow wild in Europe: Acanthus (spinosus and mollis, whose pinnatifid leaves served as models for the capitals of the Corinthian columns). The posterior sepal is the largest of all the leaves of the flower, and covers the other parts like a helmet; the 2 anterior sepals are united, and the two lateral ones are small and greenish; the corolla has no upper-lip, but only a 3-lobed under-lip. The anthers are bilocular; the filaments ultimately become very firm.--Justicia, Eranthemum, Goldfussia, Thunbergia (a twiner), Ruellia, Dicliptera, etc.--Ornamental plants in conservatories.

Order 9. =Plantaginaceæ= (=Plantains=). The flowers (Figs. 570, 571) are regular, ☿, hypogynous, with a =4=-partite, persistent calyx, a gamopetalous, scarious corolla with =4= projecting lobes, =4= stamens, incurved in the bud, later on projecting considerably, about equal in length, and a bilocular ovary with one long, filamentous, undivided, feathery, papillose style (see Fig. 571). The ovary is most frequently bilocular with 1–few ovules in each loculus. An hypogynous disc is wanting. The fruit is a pyxidium with 1–few peltate seeds attached in each loculus (Littorella is in several respects an exception). All species are herbs, the majority with leaf-rosettes near the ground, and the flowers in spikes or capitula.

The labiate-like flowers are in this case entirely concealed under a regular, apparently 4-merous exterior. The structure of the flower, however, is the same as in the Scrophulariaceæ, only the reduction, which is found in Veronica (compare Figs. 562 C, 567 with 570, 571), is also present in this instance and the lobes are also more equally developed; the posterior petal corresponds to the bilobed upper-lip; the posterior stamen and the posterior sepal also are entirely wanting. In the development of the flower there is no trace of posterior sepal or stamen, and the posterior petal arises from one primordium, but the two anterior sepals arise before the lateral ones. The position of sepals and petals does not agree with that of a true 4-merous flower, which is represented in Fig. 361 E. The bracteoles are always suppressed in Plantago.

Plantago (Plantain, Rib-grass). The foliage-leaves are most frequently scattered, entire, with curved veins, arranged in a rosette close to the ground on an unlimited rhizome; the spike-like inflorescence is borne on a long scape; in some (P. psyllium) the leaves are opposite on a stem with well-developed internodes, and the inflorescences are borne in their axils. The order also presents a transition from insect-pollinated to wind-pollinated flowers. ~The flowers are protogynous, wind-pollinated in P. major and P. lanceolata, partly also in the other species, but insect pollination also occurs, and P. media has three kinds of flowers, some of which are adapted for wind-pollination (Fig. 571), others, with short filaments, for insects.~ Littorella lacustris (Shore-weed) is the most reduced of the Plantaginaceæ: an aquatic plant with rosettes of round, awl-like leaves and diclinous (monœcious) flowers. ~In the axils of the foliage-leaves is a very short 3-flowered spike, formed by 2 sessile ♀-flowers, and above them a long-stalked ♂-flower; all the flowers are lateral, the terminal one being absent, as in Plantago. The ♂-flower is essentially the same as in Plantago, but the ♀-flower has a scarious corolla, with a narrow, 3–4-dentate mouth, which closes tightly round the nut-like fruit.~

The genus Plantago constitutes nearly the entire order (200 species). Some are widely distributed weeds (e.g. P. major, “The white man’s footstep”). In P. psyllium (S. Eur.) the integument of the seeds is mucilaginous, and swells considerably in water.

Family 31. =Nuculiferæ.=

The flowers are hypogynous and zygomorphic (in Boraginaceæ and Cordiaceæ, however, they are regular, except Echium and Anchusa arvensis). The calyx is gamosepalous, the corolla bilabiate (except in the two orders mentioned), mostly after 2/3, i.e. divided into a 2-leaved posterior portion, and a 3-leaved anterior portion. The æstivation of the corolla is nearly always descending.--In Boraginaceæ and Cordiaceæ there are 5 stamens of equal length; in the other orders 4 didynamous ones, or only 2 fertile; the posterior stamen is sometimes developed as a staminode, sometimes fertile (in Stilbaceæ). The ovary is formed of 2 median carpels (except some Verbenaceæ), with (1-) =2= ovules on each carpel; in the majority of the orders it is, however, divided by a false partition-wall between the dorsal and ventral sutures, into =4= loculi, each of which is often raised independently, causing the style to be situated in the depression between the four lobes (“gynobasic” style, Figs. 572, 573, 575, 579). The fruit in these orders most frequently becomes a 4-partite schizocarp with nut-like fruitlets. The other orders have a 1(-2)-locular ovary.--The leaves are simple, without stipules.

The family is related to (and proceeds from) the Tubifloræ, especially Convolvulaceæ, which has an almost similar construction of the ovary. It is doubtful whether the Cordiaceæ and Boraginaceæ should be classed with the others.

The orders are: 1, Cordiaceæ; 2. Boraginaceæ; 3, Verbenaceæ; 4, Labiatæ; 5, Selaginaceæ; 6. Globulariaceæ; 7, Stilbaceæ.

Order 1. =Cordiaceæ= unites Convolvulaceæ and Boraginaceæ. Tree-like plants with 5-(4–10) merous flowers, doubly bifid style, and drupe with 4 or less loculi. No endosperm; cotyledons folded.--185 species; tropical.

Order 2. =Boraginaceæ.= The vegetative parts are very characteristic: herbs with cylindrical stems and scattered, undivided, nearly always sessile, entire leaves, without stipules, and generally, together with the other green portions of the plant, covered with stiff hairs, consequently rough and often even stinging (hence the other name for the order Asperifoliæ). The inflorescences are unipared scorpioid cymes with the branches coiled spirally (“helicoid,” Fig. 573) before the flowers open. The flower is perfect, regular (obliquely zygomorphic in Echium and Anchusa arvensis), hypogynous, gamopetalous: S5, P5 (often with ligular outgrowths), A5, G2, but each of the two loculi of the ovary becomes divided by a false partition-wall into two, each of which contains one pendulous anatropous ovule with the micropyle turned upwards; the four loculi arch upwards, so that the ovary becomes 4-lobed, and the style is then, as in the Borageæ, placed at the base (“gynobasic”) between the four projections (Figs. 572, 573). The fruit is a 4-partite schizocarp with four nut-like fruitlets (Fig. 572).--Endosperm is wanting (except in Heliotropium); the radicle is turned upwards.

The INFLORESCENCES are often double unipared scorpioid cymes; the bud of the second bracteole is developed, that of the first suppressed; in some cases both the bracteoles are suppressed (Myosotis, Omphalodes, etc.), but in other instances all the first bracteoles (a) only are suppressed, and the others are then situated in two rows towards the under side of the coiled axis, while the flowers are situated on the upper side. Displacement of the branches or of the floral-leaves sometimes takes place. The flowers are often red at first, and later on become blue or violet; they hardly ever have any smell. The fruit entirely resembles that of the Labiatæ, but the radicle of the latter is turned downwards. The fruitlets present small differences which have systematic importance; they are hollow or flat at the base, attached to a flat or columnar receptacle, etc.

=1.= HELIOTROPIEÆ. This group deviates from the characteristics mentioned above in the undivided ovary and terminal (“apical”) style. In this, as well as in the fact that in some genera (Tournefortia, Ehretia, etc.) the fruit is a drupe, it connects this order with the Cordiaceæ. Heliotropium, Tiaridium, and others have schizocarps.

=2.= BORAGEÆ, BORAGE GROUP. Style gynobasic; fruit a schizocarp.

=A.= The throat of the corolla is without ligules, or with very small ones.--Pulmonaria (Lung-wort); funnel-shaped corolla; a whorl of hairs in the corolla-throat.--Echium (Viper’s-bugloss) has zygomorphic flowers, the plane of symmetry almost coinciding with that of the very well-developed inflorescence (through the fourth sepal); the corolla is obliquely funnel-shaped, the style is more deeply cleft at the apex than in the others; stamens 2 longer, 2 shorter, and 1 still shorter.--Cerinthe has a tubular corolla with five small teeth and two bilocular fruitlets. The bracts are large and leafy, and, like all the rest of the plant, are almost glabrous.--A few Lithospermum-species have a naked corolla-throat; others have small hairy ligules, which do not close the corolla-throat. The fruitlets are as hard as stone, owing to the presence of carbonate of lime and silica.--Mertensia (Steenhammera); Arnebia; Nonnea (small ligules).

=B.= The corolla-throat is closed by, or in any case provided with ligules, i.e. scale-like bodies or small protuberances, situated in the throat of the corolla opposite the petals, and which are invaginations or internal spurs of the petals (Fig. 572 D).--The nuts in Cynoglossum (Hound’s-tongue) bear hooked bristles over the entire surface, or, in Echinospermum, only on the edge. The following have smooth nuts:--Symphytum (Comfrey) has a cylindrical, campanulate corolla, and prolonged-triangular, pointed ligules.--Borago (Borage) has a rotate corolla with projecting, emarginate ligules; the stamens have a horn-like appendage, projecting upwards from the back of the filament. The fruitlets are hollow below.--Anchusa (Alkanet, Fig. 572). The corolla is salver-shaped; the ligules small, hairy protuberances. A. (Lycopsis) arvensis has an S-curved corolla-tube.--Myosotis (Forget-me-not, Fig. 573); rotate corolla with small (yellow) protuberances in the throat; scorpioid cyme without floral-leaves; fruitlets flat.--Omphalodes; fruitlets hollow at the back, with a scarious, turned-in, toothed edge.--Asperugo (Mad-wort); the calyx grows after flowering, becoming large, compressed, and deeply bifid.

CROSS-POLLINATION is most commonly effected by insects (especially bees). There are a great many contrivances for pollination; some flowers are protandrous (Echium vulgare, Borago officin.), others are heterostylous (long-and short-styled: Pulmonaria officin.); the corona (ligules) is a protection against rain, and excludes certain insects. Some are barren when self-pollinated (Pulmonaria officinalis, Echium vulgare); others which have but little honey, may, failing insect-pollination, fertilise themselves, and in Myosotis versicolor this regularly occurs by the growth of the corolla during flowering, so that the anthers are brought into contact with the stigma. Honey is secreted on the hypogynous disc.--About 1,150 species, growing especially in the northern temperate zone, Mucilage is found (e.g. in the officinal root of Cynoglossum officinale, in the root of Symphytum): red dyes are found in some roots (e.g. Alkanet-root, the root of Alkanna tinctoria, which is also medicinal; S. E. Europe, Asia Minor); some are poisonous: Cynoglossum, Echium, Anchusa, etc. Several species are ornamental plants. Heliotropium (Peru) is cultivated chiefly on account of its pleasant scent; essential oils are otherwise very rare.

Order 3. =Verbenaceæ.= The majority are shrubs; a few are herbs or trees (Teak-tree); some are lianes. The branches are often square. The leaves are opposite or verticillate, without stipules; in some compound. The inflorescences are racemes, spikes, capitula, or dichasia. Five sepals; five petals in a gamopetalous, zygomorphic corolla, which is often bilabiate, but rarely to such an extent as in the Labiatæ, and the upper lip in some is larger than the under, in others smaller; stamens four didynamous, or two; the ovary is entire (not grooved or divided), 1- or 2-locular, or, as in the Labiatæ, divided into four loculi with an erect ovule in each, but in some the anterior carpel is suppressed. One terminal style. The fruit is, e.g. in Verbena, a 4 partite schizocarp with nut-like fruitlets; in Vitex (digitate leaves) a drupe with a 4-locular stone; in Clerodendron a similar fruit, with four free stones; in Lantana a bilocular stone, or two unilocular stones. The radicle is turned downwards. Endosperm small or absent.--Lippia, Stachytarpheta, Bouchea, Priva, Citharexylon, Callicarpa, etc.--The Verbenaceæ are closely allied to the Labiatæ; they differ especially in the ovary not being 4-lobed with gynobasic style, but undivided, almost spherical or ovoid with a terminal style. Again, the leaves are not so constantly opposite, and the inflorescences are various.

730 species; especially in the Tropics; there are several in America, especially Lantana-species; shrubby weeds.--Many of those mentioned are ORNAMENTAL PLANTS, especially Verbena; Vitex agnus castus is a S. European shrub. Lippia citriodora (S. Am.) etc., have strongly-scented leaves; the Teak tree (Tectona grandis) is one of the largest trees in East India, and has a very hard wood.

Avicennia is allied to this order; it inhabits the Mangrove swamps on tropical coasts. The endosperm emerges from the ovule, carrying the embryo with it; the embryo ultimately bursts the endosperm and lies free in the loculus of the fruit; this is then filled by the embryo with its large, green cotyledons, which are borne on an already hairy or rooted stem. The seedling thus developed falls from the tree, together with the fruit, and strikes root in the mud. One special cell of the endosperm at an earlier period becomes a highly-developed organ of suction, growing into a much-branched sac, very rich in protoplasm.

Order 4. =Labiatæ.= The special characteristics are: the square stem, the opposite leaves (without stipules), the inflorescences which are formed by two double unipared scorpioid cymes, the labiate corolla, the 4 didynamous stamens (the posterior being entirely suppressed) (Fig. 574), and the 4-partite schizocarp with nut-like fruitlets. The floral formula is S5, P5, A5 (the posterior stamen is generally absent), G2.

They are chiefly aromatic plants (herbs, shrubs, e.g. Lavender, or trees), volatile oil being formed in internal cells or in the glandular hairs, which cover all green parts. The stem is always more or less markedly square; the leaves are borne upon the flat sides, and are simple and penninerved, but vary in the other characters. The inflorescences are double unipared scorpioid cymes, which may be situated at some distance from one another in the axils of the foliage-leaves (Fig. 575 A), but frequently when the subtending leaves are bract-like, they are crowded into spike-like inflorescences (Lavandula, Mentha, Salvia, etc.), each of the so-called “whorls” (verticillaster, glomerulus) being a double unipared scorpioid cyme (Fig. 574). (Solitary flowers are found in e.g. Scutellaria, and Origanum). The calyx is strongly gamosepalous, 5-toothed, often bilabiate (Fig. 575 B). The corolla is strongly bilabiate (Figs. 575, 576, etc.), with 2 lobes in the upper lip and 3 lobes in the under lip (an approach to regularity occurs only when the upper lip is small, and thus resembles one lobe, as in Mentha (Fig. 578) and Lycopus, so that the corolla approaches the 4-merous corolla of Veronica and Plantago). The posterior stamen in the diagram (Fig. 574*) is entirely suppressed; in most of the genera the posterior lateral stamens are the smaller (Fig. 575 D), and are entirely suppressed in some (see below); in others, e.g. Nepeta, they are the longer. 2 stamens are found in Salvia, Rosmarinus, Lycopus, etc. The two halves of the anthers are often separated from one another, and are placed at an angle with each other. The gynœceum has 1 style with a bifid extremity (Fig. 575 C) bearing the stigma; the true bilocular ovary is divided by a false partition-wall into 4 loculi, each with 1 erect ovule (Fig. 575 H). These 4 loculi project so strongly that the ovary becomes deeply 4-lobed with the style situated in the centre of the lobes and at their base, “gynobasic” (Figs. 575, 579). A ring-like, often crenate, nectary surrounds the base of the ovary (Fig. 575 G, H). The embryo in this order, as in the Verbenaceæ, is directed downwards (Fig. 575 J) (it is directed upwards in the Boraginaceæ, which have an entirely similar fruit). Endosperm absent.

The 142 genera are mainly distinguished according to the form of the calyx and corolla, the number, direction, and length of the stamens, the forms of the nuts, etc.

=1.= AJUGEÆ, BUGLE GROUP. Calyx 10-nerved; the upper lip is small; 4 stamens. The ovary is not so strongly lobed as in the following group, so that it is most nearly allied to the Verbenaceæ. The nuts are reticulately wrinkled. Ajuga (Bugle) has a very small upper lip. The upper lip of Teucrium (Germander) is deeply cleft, and the two lobes are bent on their respective sides towards the under lip, which in consequence appears to be 5-lobed, and the upper lip to be wanting.

=2.= STACHYDEÆ, BETONY GROUP. The calyx is 5- or 10-nerved. The upper lip of the corolla is most frequently strongly arched or helmet-shaped; 4 stamens, the anterior pair the longer (Fig. 576).

=a.= A somewhat regular and 5–10-dentate calyx with projecting stamens.--Stachys (Betony, Woundwort); the lobes of the under lip are rounded off. The anterior filaments, after pollination, bend outwards. Betonica--Ballota (Horehound); the calyx is funnel-shaped, and has triangular, long, pointed, awn-like teeth.--Galeopsis (Hemp-nettle) has two conical protuberances on the under lip between the lateral and the central lobes. The anthers open by 2 unequal valves. Lamium (Dead-nettle, Fig. 576) has dentate, lateral lobes on the under lip. L. album (White Dead-nettle), L. rubrum, etc. Galeobdolon.--Leonurus; Phlomis.

=b.= Tubular, regular, often 10-toothed calyx and concealed stamens.--Marrubium vulgare (Fig. 577); 10 calyx-teeth, hooked at the apex; many almost spherical whorls of flowers in the axils of the foliage-leaves, at some distance from one another.--Sideritis.

=c.= Strongly bilabiate calyx, the lips closing together after flowering.--Scutellaria (Skull-cap); the two lips of the calyx are entire, the upper lip has a large spur, and drops off on the ripening of the fruit. The flowers are generally solitary and turned to one side.--Prunella (Heal-all); the calyx is compressed, its two lips are strongly dentate, the upper lips closing slightly round the under. The stamens have a tooth-like projection beneath the anthers.

=3.= NEPETEÆ, CATMINT GROUP. 13–15 nerves in the calyx; this deviates from the other groups in the posterior stamens being the longer. The upper lip is slightly arched. Nepeta (Catmint), also Glechoma (Ground Ivy), with regular, and Dracocephalum with irregular calyx.

=4.= SATUREIEÆ, MINT GROUP. The upper lip is flat, most frequently ovate, or almost spherical, and emarginate (Fig. 578). The calyx is most frequently 5–10-nerved. 4 stamens, the anterior being the longer; rarely, 2 stamens only.--Mentha (Mint, Fig. 578) has a regular, 5-dentate calyx, a small, almost regular, 4-partite corolla, and 4 erect stamens of nearly equal size. The verticillasters are many-flowered, and are often collected into cylindrical inflorescences. Herbs.--Lycopus (Gipsy-wort); corolla almost regular. 2 stamens, the posterior lateral ones are wanting. Preslia: 4-dentate calyx, 4-partite, regular corolla; 4 stamens of equal size.--Thymus (Thyme, Fig. 575) has a strongly bilabiate calyx, the throat being closed by a whorl of hairs (Fig. 575 B). The corolla is distinctly labiate. Under-shrubs, with small entire leaves; verticillasters few-flowered and separate.--Origanum (Marjoram); spike or capitate inflorescences with the flowers solitary in the axils of the rather large and distinctly 4-rowed (often slightly coloured) floral-leaves. Melissa. Calamintha. Clinopodium (Wild Basil). Satureia. Hyssopus (Hyssop); small, entire leaves; the verticillasters are situated unilaterally in a slender, spike-like inflorescence. Lavandula (Lavender); shrubs with verticillasters collected in cylindrical, long-stalked inflorescences; the calyx is tubular, has 13–15 nerves, the posterior tooth is much larger than the others. Stamens and style do not project. ~Coleus differs, among other characters, in having united filaments; the stamens and style are bent down and concealed in the boat-shaped under lip.~

=5.= MONARDEÆ, SALVIA GROUP. Only the 2 anterior stamens are developed.--Salvia (Fig. 579); calyx deeply bilabiate; the upper lip of the corolla is generally strongly compressed. Rudiments of the two lateral stamens are present. The connective in the two fertile stamens is long and filamentous, and bears at the upper end a normal half-anther, but at the lower one a barren, often broader portion, against which the insect is obliged to push its proboscis during its visits to the flowers, causing the pollen-bearing half-anther to be pressed down against its back. Floral-leaves often coloured.--Rosmarinus (Rosemary); a shrub with leathery linear leaves, with rolled back edge. A small tooth on the filament represents the barren half of the anther. Monarda.

The POLLINATION is generally effected by insects, especially bees; the under-lip is the landing-stage and the pollen is deposited on their backs. Cross-fertilisation is promoted by dichogamy; honey is secreted by an hypogynous disc and collected in the corolla-tube. Some genera are homogamous (Lamium, Galeopsis, etc.); others are dichogamous (protandrous); a few are gynodiœcious: ♀-and ☿-flowers in various relative sizes (Glechoma hederaceum, Thymus, Salvia pratensis, and others). The entrance of uninvited guests to the honey is often rendered difficult by whorls of hairs, etc. In numerous instances the upper lip protects the pollen from rain. Cleistogamy is found e.g. in Lamium amplexicaule.

2,700 species; distributed over the entire globe, but the greater number in Mediterranean countries (especially in the Eastern regions), where many are shrub-like.--Poisonous and acrid properties are absent. On account of their volatile oils they are principally used as condiments, for perfumery and in medicine (the officinal parts are therefore nearly always “folia” and “herba,” in Lavandula the flowers, and the volatile oils extracted from them). Such are:[39]Mentha piperita [+] (Peppermint)--menthol is obtained from this species and from M. arvensis--M. viridis [+] (Spearmint), M. crispa (Curly-mint), Thymus vulgaris (Garden Thyme), Melissa officinalis (S. Eur.), Hyssopus officinalis (Hyssop, S. Eur.), Origanum majorana (Marjoram, from the Mediterranean), O. vulgare (Wild Marjoram), creticum, smyrnæum, etc., Salvia officinalis (S. Eur.), Rosmarinus officinalis (oil of Rosemary, S. Eur.), Lavandula vera [+] (oil of Lavender, S. Eur.). Also: Satureia hortensis (S. Eur.), Ocimum basilicum (E. India), Pogostemon patchouli (E. India), etc.--As ornamental plants, e.g. Monarda, Plectranthus, and Coleus (foliage-plants, often with red stems and leaves), Stachys lanata (white, woolly), Phlomis, Salvia-species, Perilla, etc.

Order 5. =Selaginaceæ.= 130 species; small, most frequently heath-like shrubs or herbs, mainly from S. Africa. They differ from the other Nuculiferæ especially in the bilocular, transversely-placed anthers of the 4 stamens (2 stamens divided as far as the base (?)). The ovary has 2, or by suppression only 1 loculus, each with 1 ovule, and the fruit is a schizocarp dividing into two, or is a 1-seeded nut. Radicle turned upwards.--A few are ornamental plants (Selago, Hebenstreitia).

Order 6. =Globulariaceæ.= 12 species; especially in the Mediterranean. They form an analogy to the Compositæ, and in the main resemble Jasione montana in appearance, the flowers being crowded into a spherical head (hence their name) and supported by bracts, but without involucre; the ovary is unilocular with 1 pendulous ovule. The 1-seeded nut is enveloped by the persistent calyx. The corolla is more or less labiate, the upper-lip is often absent as in the ligulate corollas of the Astereæ; stamens 4, didynamous, with transversely placed anthers opening by one transverse cleft. The leaves are scattered, simple, entire, and generally form a rosette. Globularia.

Order 7. =Stilbaceæ.= Heath-like shrubs. The ovary is bilocular; 1 erect seed in each loculus, or the posterior cell is empty. Stilbe. 7 species. S. Africa.

Family 32. =Contortæ.=

Hypogynous, regular, ☿, gamopetalous flowers (Figs. 581, 582), which are generally 5- or 4-merous, with 5 or 4 stamens (with the exception of Oleaceæ and Jasminaceæ which have only 2 stamens, alternating with the carpels). The gynœceum is formed of 2 (nearly always median) carpels. The corolla very frequently has twisted æstivation (the upper edges of the petals being free; Fig. 581 A), and hence the individual lobes of the corolla are oblique, but the flower as a whole is regularly actinomorphic. A nectary, in the form of a honey-secreting ring or glands, is often found round the base of the ovary.--The leaves, with a few exceptions, are opposite and without stipules. Endosperm large (Fig. 581 C), except in Jasminaceæ and Asclepiadaceæ.

The Apocynaceæ and the Asclepiadaceæ, on account of the free ovaries, without doubt represent a more primitive form, but the Asclepiadaceæ on the other hand form an offshoot on account of their peculiar pollen-masses. The Loganiaceæ form a transition to the Rubiaceæ.

The orders are:--

A. STAMENS 5. 1, Gentianaceæ; 2, Apocynaceæ; 3, Asclepiadaceæ; 4, Loganiaceæ.

B. STAMENS 2. 5, Oleaceæ; 6, Jasminaceæ; 7, Salvadoraceæ.

Order 1. =Gentianaceæ= (=Gentians=). Glabrous herbs, without latex; the opposite, undivided and entire leaves are often slightly united at the base; many have rosette-like radical leaves. Stipules absent. The flowers are generally borne in regular, dichotomously-branched dichasia (Figs. 580, 581 A), which finally become transformed into unipared scorpioid cymes; the parts of the flower are 4–5-merous as far as the gynœceum, which is 2-merous; the calyx frequently is almost polysepalous; the corolla has distinctly twisted æstivation (the upper edges being free) (Fig. 581 A), except Menyantheæ. The carpels are entirely united, and most frequently form a 1-locular ovary with 2 parietal placentæ bearing many ovules (often in several rows, Fig. 581 D, F). Capsule, 2-valved, with septicidal dehiscence, the incurved edges bearing the seeds (Fig. 581 D, F).

=1.= GENTIANEÆ.--Gentiana (Gentian) has most frequently a tubular, campanulate or funnel-shaped corolla, sometimes with teeth between the corolla-lobes and fringed in the throat of the corolla; G. lutea has a rotate, yellow corolla.--~Swertia: rotate corolla; each lobe has at its base 1–2 nectaries, with fringed edges.~

Erythræa (Centaury, Fig. 581); corolla most frequently salver-shaped. The anthers ultimately become spirally twisted (E). The style prolonged, deciduous. The flower has the Lobelia-arrangement, i.e. the median sepal is anterior; the corolla is rose-coloured (in the native species). The capsule is semi-bilocular (Fig. 581 F, G).--~Cicendia has a low creeping stem, fine as a thread, and small, yellow flowers, 4-merous (without twisted anther).--Chlora (Yellow-wort) 6–8-merous.~

=2.= MENYANTHEÆ. Menyanthes (Buck-bean) deviates in several respects from the type of the order. The leaves are scattered and, in M. trifoliata, trifoliate; the corolla has valvate æstivation; the testa is also very hard (thin in the true Gentians). They are aquatic plants with creeping rhizome; the flowers borne in racemes, with terminal flower, heterostylous. The corolla is funnel-shaped with a very hairy throat.--~Limnanthemum with floating leaves, like the Water-lilies.~

575 species; distributed over the entire globe, but most numerous in Alpine districts. Neither poisonous nor nutritive plants are found, but several are used in medicine on account of the bitter properties so prevalent amongst them. OFFICINAL: the roots of Gentiana lutea. The roots of other species, e.g. G. purpurea, punctata and pannonica (Europe) and the leaves of Menyanthes trifoliata are medicinal. Some are grown as ornamental plants on account of the pure (often deep blue) colour of the flowers.

Order 2. =Apocynaceæ= (=Periwinkles=). Trees and shrubs (also lianes), less frequently herbs, generally with latex. The leaves are opposite, simple, entire, without stipules; the flowers are regular; corolla-lobes oblique, æstivation twisted. The stamens are individually free, and the pollen-grains are free or at most united in fours (see Asclepiadaceæ). The two carpels have 2–∞ ovules, in all cases there is only 1 style and a capitate stigma, which towards the base is widened out into a disc-like table (stigma-disc) abstricted in the centre; but the carpels in most of the genera (e.g. those mentioned below) are entirely separate, and the fruit consists of two follicles, the seeds of which often have a tuft of woolly hairs projecting from the micropyle, less frequently of two drupes. In some other genera there is a 1-locular (provided with 2 parietal placentæ) or a 2-locular ovary becoming a 2-valved capsule or a berry. Endosperm abundant.

Vinca (Periwinkle) has a salver-shaped corolla, which is twisted to the left in æstivation (i.e. the left edge of the petals is free); nectaries 2, alternating with the carpels; the summit of the style is hairy. Follicles; seeds without hairs. ~Mostly creeping, perennial, evergreen plants, whose large flowers are apparently axillary; in reality they are terminal, but by the development of the bud in the axil of one of the two uppermost leaves, they are thus displaced over the other leaf of the pair (a helicoid sympodium being formed).--Plumeria, Tabernæmontana, Cerbera (drupe). Aspidosperma.~

Nerium (Oleander). The leaves are in whorls of 3. Corolla funnel-shaped, in æstivation twisted to the right, and with a corona resembling that of Lychnis. The anthers are prolonged at the base and each also bears at the apex a long, linear, hairy appendage; these finally become spirally twisted. Follicles; seeds hairy. Apocynum, Echites, etc. Epigynum is epigynous.

124 genera, 1,000 species; principally in the Tropics. Only 2 species of Vinca are natives of this country; the following are cultivated as ornamental plants:--Vinca minor, V. major, V. (Lochnera) rosea, Amsonia salicifolia, Nerium oleander (Eastern Mediterranean). The latex of some is poisonous (Tanghinia venenifera, Cerbera). Caoutchouc is obtained from others (Hankornia, Landolphia, Vahea, etc.). Tough bast is frequently developed. The bark of Aspidosperma quebracho and the seeds of Strophanthus hispidus are used in medicine (also for African arrow-poison), the latter is officinal.

Order 3. =Asclepiadaceæ.= A natural and easily recognised order, closely allied to the Apocynaceæ, having, like it, frequently a poisonous latex, opposite, single, entire leaves and fundamentally the same floral diagram and floral structure (S5, P5, A5, G2); but in some the æstivation of the corolla is valvate. The carpels here also have free ovaries, but are united for some distance above into a large, shield-like, 5-angular head, having on its underside the true stigmas, and the fruit always consists of 2 follicles; seeds most frequently numerous and hairy at the micropyle (“vegetable silk”); endosperm scanty.--The order is distinguished from the Apocynaceæ and from all other plants also, except the Orchids, by having all the pollen-grains in each of the =2= loculi of the anthers (true 2-locular anthers) united into one waxy, club-shaped pollen-mass (“pollinium”), for the purpose of pollination by insects. These heavy masses, in order to secure pollination (as in the case of the Orchids), must be attached to sticky discs (corpuscula); there are 5 corpuscula, one at each of the corners of the 5-angular stylar-head (alternating with the anthers), and to each of these are attached 2 pollinia, one from each of the anthers situated on either side (thus each anther gives its right pollinium to one corpusculum and its left to another). The stamens are frequently united at the base, and each bears on the back a variously formed, petaloid appendage, termed a “cucullus.”

A peculiar relative position (and therefore a good, distinctive characteristic) is often found in the inflorescence, which is cymose; it is placed between the two leaves of a whorl, nearer to one than to the other. ~The leaf-pairs are placed obliquely in the floral region, at acute and obtuse angles, and not at right angles (as in the purely vegetative parts); the inflorescences are placed in two rows only which are nearly 90° from each other, and the two contiguous to one another are antidromous; they are in reality terminal, each on its own axis, and the entire floral portion of the shoot is a unipared scorpioid cymose sympodium; in addition, complications also arise through individual parts becoming united.--Herbs and shrubs, some twining or climbing.~

In Asclepias the corolla is bent back and there is a cup-like cucullus, from the base of which protrudes a horn-shaped body, bent inwards.--Vincetoxicum has a rotate corolla and a ring-like, 5-lobed cucullus, without internal prominences.--~Stapelia (especially from S. Africa) is remarkable on account of its Cactus-like, leafless stems and large, brownish flowers, often with carrion-like smell. Periploca has more powdery pollinia (S. Eur., etc.); Hoya carnosa (Wax-flower; Trop. Asia) is a climber, and has small, annual, flower-bearing dwarf-branches. Ceropegia.~

201 genera with 1700 species, distributed over all tropical countries; few outside these limits: no native species. Several are used in medicine on account of the pungent properties of the latex. Condurango-bark of Gonolobus condurango is medicinal. Caoutchouc is obtained from the latex of some (e.g. from Cynanchum). The seed-hairs, which are most frequently shining, silk-like, and white, are not sufficiently pliant to be of much value. Ornamental plants in our gardens: Asclepias-species, etc.

Order 4. =Loganiaceæ.= Ovary single, with two loculi, in structure resembling the Rubiaceæ, but superior. 360 species are included in this order; the majority are tree-like, some lianes which climb by tendril-like branches. The interpetiolar stipules of some species are very characteristic (as in Rubiaceæ, to which they maybe considered to be closely related). The fruit is a capsule or berry. The most familiar genus is Strychnos, which has spherical berries with an often firm external layer, and compressed seeds with shield-like attachments; endosperm abundant. The leaves have 3–5 strong, curved nerves proceeding from the base.--Spigelia.--They have no latex, as in the two preceding orders, but many are very poisonous (containing the alkaloid “strychnine,” etc.); the South American arrow-poison, urare or curare, is made from various species of Strychnos, also an arrow-poison in the East Indian Islands (Java, etc.). OFFICINAL, the seeds of Strychnos nux vomica (“Vomic nut,” Ind.). The seeds of Strychnos ignatii (Ignatius-beans, medicinal), and others are poisonous.

Order 5. =Oleaceæ.= The leaves are always opposite. The inflorescences are racemes or panicles. The calyx and corolla are 4-merous, more or less united, free in some species; the corolla has most frequently valvate æstivation. All four forms of fruit occur (see the genera). Ovules pendulous, 2 in each loculus (Fig. 583 C). Endosperm oily.--Syringa (Lilac) and Forsythia (anthers somewhat extrose) have capsules with loculicidal dehiscence and winged seeds.--Fraxinus (Ash) has winged nuts (samara) (Fig. 583 D); trees with most frequently imparipinnate leaves; the flowers are naked and sometimes unisexual (polygamous), the Manna Ash (F. ornus) has however a double perianth with 4 free petals (Fig. 583 a); in the native species, F. excelsior, the flowers open before the foliage appears.--Ligustrum (Privet) has berries.--Olea (O. europæa; Olive) has drupes; the pulp and seeds of the ellipsoidal fruits are rich in oil. The lanceolate leaves are grey on the under surface, being covered with stellate hairs. In the wild state it is thorny (modified branches).--Phillyrea; Chionanthus.--Few species of Linociera have 4 stamens.

180 species; chiefly in the northern temperate zone. The Olive-tree (Olea europæa) has been an important cultivated plant from ancient times (Olive oil, Provence oil, “Sweet oil”). The best oil is extracted from the fruit-pulp. The fruits are edible. Home: Western Asia, Eastern Mediterranean. TIMBER: the Ash (Fr. excelsior). OFFICINAL: the Manna Ash (Fr. ornus), cultivated in the Mediterranean countries for the sake of its saccharine juice, which flows out and coagulates into “Manna.”--The following are ornamental plants: species of Ligustrum and Syringa (introduced in the 16th century, from S.E. Europe and Asia), Forsythia (China, Japan; the large, yellow flowers are borne on dwarf-branches with scale-like leaves, before the opening of the foliage-leaves), Chionanthus.

Order 6. =Jasminaceæ.= The æstivation of the corolla is imbricate; the ovules are erect; seeds almost without endosperm; radicle directed downwards. The number of lobes in the calyx and corolla is not 4, but e.g. 5, 8, 10, and variations are sometimes found in the same individual. The fruit is a berry or capsule. Many species are twiners, and their scattered or opposite leaves are most frequently imparipinnate.--120 species; especially in Trop. Asia (E. India). Some Jasminum-species are cultivated as ornamental shrubs in the warmer districts on account of their elegant foliage, and beautiful, sweet-scented flowers, the essential oil of which is also used in perfumery; the best known are: J. sambac and grandiflorum. Nyctanthes arbor-tristis opens its sweet-scented flowers only at night (E. India).

Order 7 (?). Salvadoraceæ. 8–9 species; Asia, Africa.--Salvadora.

b. Tetracyclicæ with epigynous flowers.

Family 33. =Rubiales.=

The leaves are always opposite or verticillate. The flower is epigynous, ☿, 5-(or 4-) merous, with the usual sympetalous diagram; 2–5 carpels. The inflorescences are frequently dichasial. The sepals are small, reduced to teeth, and become almost entirely suppressed in the higher forms.--The flower is regular in Rubiaceæ and some Caprifoliaceæ, but in other genera of this latter order (especially of Lonicereæ) it is unsymmetrical. In several genera of the order first mentioned the loculi of the ovary contain many ovules, but in the last the number of loculi and ovules becomes reduced. This is to some extent connected with the nature of the fruit which is many-seeded in most instances, namely a capsule or berry, but in others nut-like. Endosperm is present.

The family on one side is allied to the Contortæ (not only through the Loganiaceæ but also through the Apocynaceæ), and may be regarded as an epigynous continuation of this family; on the other side it is allied to the Valerianaceæ and Dipsacaceæ. Many points of agreement with the Cornaceæ and Araliaceæ are also found, and in fact several Caprifoliaceæ are distinguished from these by hardly any other feature than the gamopetalous corolla.

Order 1. =Rubiaceæ.= Leaves opposite (or verticillate), undivided and entire, with interpetiolar stipules (Fig. 586). Flowers epigynous and hermaphrodite, regular, 4- or 5-merous with the usual arrangement (Figs. 585, 588–590); corolla gamopetalous, in æstivation often valvate; ovary frequently 2-locular.

There are no external characters which at once distinguish this exceedingly large order, as in many other natural orders (Compositæ, Umbelliferæ, etc.), but the opposite leaves with interpetiolar stipules form an excellent mark of recognition. It is divided into many sub-orders and groups, especially characterised by the nature of the ovary (1 or several ovules in each loculus), and of the fruit (schizocarp, berry, drupe, capsule).--The corolla is bilabiate in 4 genera; its æstivation in some is twisted; in Capirona, etc., the filaments are of unequal size. The ovary is semi-epigynous in Henriquezia, etc. In Morinda all the fleshy fruits coalesce into one multiple fruit.

=1.= CINCHONEÆ. The fruit is a 2-valved capsule, with many winged seeds (Fig. 585). Cinchona (Quinine, Fig. 584). Trees and shrubs with the foliage and inflorescence somewhat resembling Syringa; the corolla also being of a lilac colour, more or less salver- or funnel-shaped, and frequently edged with a fringe of hairs (Fig. 585), is somewhat similar to that of Menyanthes. Their home is the Andes from Bolivia to Venezuela, varying in altitude from 1–3000 metres. There are now large plantations in Java and E. India. ~(The name “quinine” is of Indian origin; that of the genus “Cinchona,” is from the Spanish Duchess Cinchon, who in 1638 first introduced the bark into Europe.) The following are closely allied: Cascarilla, Remijia, Ladenbergia, Manettia, Bouvardia, etc.~

=2.= GARDENIEÆ. Trees and shrubs, frequently having a many-locular berry. Randia, Gardenia, Genipa, Hamelia, etc.

=3.= COFFEEÆ. Only 1 seed in each of the two loculi of the ovary; the fruit is a drupe with 2 stones. Coffea has an ellipsoidal fruit about the size and colour of a cherry; the two thin-shelled, parchment-like stones are enclosed by a thin layer of pulp; the two seeds are flat on the side turned to one another, which has also a deep, longitudinal groove curving to the sides. The endosperm is hard, horny and greyish (without starch); the small embryo lies in the lower end near the circumference. The Coffee-plant (C. arabica) is a small tree, or more frequently, and especially in plantations, a shrub with large dark-green leaves and scented, white flowers. Its home is in Tropical Africa; it is now cultivated in many tropical countries. C. liberica, W. Africa.--Cephaëlis (C. ipecacuanha, Fig. 586; the roots are officinal).--~Psychotria, Chiococca, Ixora, Hydnophytum, Myrmecodia, etc.~

=4.= SPERMACOCEÆ. Chiefly small shrubs and herbs, many of which are weeds in tropical countries. The stipular sheaths bear numerous bristles at the edge. Spermacoce, Borreria, Diodia, Richardsonia, etc.

=5.= STELLATÆ. Herbaceous plants with verticillate leaves (Figs. 587, 588–590); the stipules are large, leaf-like, and resemble the lamina of the leaves, so that the leaves appear to be placed several in a whorl, while in reality there are only two opposite leaves, the stipules of which project freely, and are not erect (Fig. 587).

In some cases there are apparently 4 leaves in the whorl, and then 2 of these are leaves, and the other two are their interpetiolar stipules. When there are apparently 6 leaves, then the two of these which are opposite each other are leaves, and the other four are stipules; if there are several members in the whorl, then a division of the stipules has taken place. The proof of this theory is founded upon the fact that not more than 2 of the leaves of the whorl ever support buds (which, in addition, are seldom of equal vigour), and also that the whorls do not alternate with each other, which, according to the rules of the position of the leaves, they should do if all the members of a whorl had equal value. If there are, for instance, 4 members in two successive whorls, they stand right above one another, and do not alternate. The development and anatomical relations (the branching of the vascular bundles) also point to the same conclusion.~--All the other groups of the order have only 2 small scale-like interpetiolar stipules, or they form at the base of the leaf-stalks an interpetiolar sheath, having often a toothed edge (Fig. 586).--Another characteristic feature in this group is that the calyx is rudimentary, the corolla valvate (Fig. 588), and that each of the two loculi of the ovary has only 1 ovule. The fruit is a schizocarp dividing into 2 fruitlets (Fig. 590). ~The forms of the fruit, as well as many other characters, as, for example, the epigynous flower, the rudimentary calyx, the two free or almost free styles, present interesting analogous resemblances to the polypetalous order of the Umbelliferæ.~ This group has its home chiefly in the temperate regions of the northern hemisphere, especially about the Mediterranean; it is the only group which occurs in this country, represented by 4 genera.

Galium (Cleavers) is almost destitute of a calyx; it has a small 4-partite, rotate corolla, 4 stamens, and 2 free styles. The fruitlets are nut-like. The inflorescence is a paniculate dichasium passing into helicoid cymes.--Asperula (Woodruff) is distinguished from the above by its salver- or funnel-shaped corolla. 1 style.--Rubia (Madder, Figs. 587–590) has almost the same form of corolla as Galium, but (most frequently) a 5-merous flower, and the fruitlets are “drupes.” ~Sherardia (Field Madder); the flowers are clustered in closely arranged cymes surrounded by an involucre; the calyx has 6 distinct teeth, while the number of petals and stamens is 4. The corolla is funnel-shaped.--Vaillantia. Crucianella.~

The DISTRIBUTION OF SEEDS, in some instances, is promoted by hooked appendages on the fruitlets (e.g. Galium aparine).

The small flowers of the Stellatæ are frequently collected in compact inflorescences, and are therefore rendered more conspicuous; slight protandry is found in some, self-pollination in the species which are less conspicuous. Many species are heterostylous. Myrmecodia, Hydnophytum, and other genera have large tubers (hypocotyledonous stems), whose labyrinthine cavities and passages are inhabited by ants.

About 4,500 species; tropical or sub-tropical except the Stellatæ; especially American. The tropical ones are mostly trees.--Several are ~OFFICINAL~ on account of the large amount of alkaloids and glycosides which they contain. The most important are the Cinchonas (Cinchona calisaya, C. succirubra, C. officinalis, C. micrantha, etc.), whose bark contains the well-known febrifuge and tonic, Quinine, Cinchonin, etc.; Quinine is also found in Exostemma, Ladenbergia, and Remijia. The root “Ipecacuanha” (an emetic) from Cephaëlis ipecacuanha (Brazils). Caffeine is officinal. The use of the seeds of the coffee plant (“the beans”) was first known in Europe in 1583.--There are only a few which contain aromatic properties, principally among the Stellatæ (coumarin in Asperula odorata, the Woodruff), in which group colouring materials are also found. The root and root-stalks of Rubia tinctorum, the Madder (S. Eur., Orient., Fig. 587), were formerly largely used for dyeing, but are now superseded by the analine colours. Red dyes are also obtained from the roots of species of Asperula and Galium. Gambier is a splendid colouring material, obtained from Uncaria gambir (S.E. Asia), which is used in dyeing and tanning.--The order does not furnish many ornamental flowers.

Order 2. =Caprifoliaceæ.= This order agrees with the Rubiaceæ in having opposite leaves and an epigynous flower, most frequently 5-merous with the ordinary tetracyclic diagram, but in some species it is zygomorphic; the corolla has imbricate æstivation, carpels 3–5, most frequently 3 (not 2, which is the most usual number in the Rubiaceæ). The fruit is generally a berry or a drupe, but the most important, and in any case most easily recognisable feature, is the absence of stipules; in exceptional cases, where they are present, they are not interpetiolar, and are most frequently small.--~The majority of plants belonging to this order are shrubs or trees. Compound leaves sometimes occur. Stipules only appear in a few species of Lonicera, Sambucus and Viburnum; in the common Elder (Sambucus nigra) they are in some instances glandular and small, but in other cases larger and more leaf-like (upon long, well-developed shoots); in the Dwarf Elder (S. ebulus) they have the normal leaf-like form; in Viburnum opulus they are present as narrow lobes at the base of the petiole; in others they are completely absent. The leaves are frequently penninerved, rarely palminerved. The calyx, as in the Stellatæ and Aggregatæ, is often very insignificant.~

=1.= LONICEREÆ, HONEYSUCKLE GROUP. This has campanulate or tubular corollas which are often zygomorphic; in connection with the length of the corolla the style is long, filamentous, and most frequently has a large, capitate stigma. There are several ovules in the loculi of the ovary, and the fruit is most frequently a berry.

Lonicera (Honeysuckle). Shrubs, sometimes twiners. The corolla in some species is considerably bilabiate (Fig. 591), with 4 lobes in the upper lip, and 1 in the under lip, but in others more regular, tubular, or campanulate. The flowers are either borne in capitate inflorescences, which are compound and formed of closely compressed 3-flowered dichasia (sect. Caprifolium), or in dichasia with 2 flowers (the terminal flower is wanting). The ovaries and fruits coalesce in some (sect. Xylosteum). ~The opposite leaves in some species unite with each other and form a broad collar encircling the stem (Fig. 591). Above the primary bud 1–2 accessory buds are often found in the leaf-axils.--Diervilla (Weigelia); with a 2-locular, 2-valved capsule.--Symphoricarpus (Snowberry) has an almost regular, funnel-shaped corolla; a peculiar feature is found in the ovary which has 4 loculi, the 2 median having many ovules in 2 rows, all of which are aborted; the 2 lateral ones, on the other hand, each have only 1 ovule which is developed. Different forms of leaves are frequently found on the same branch; they are entire or lobed.~

=2.= SAMBUCEÆ, ELDER GROUP (Fig. 592). This has a rotate, regular corolla, extrorse anthers, a very short and thick (or almost absent) style, with tripartite stigmas, and only 1 pendulous ovule in each of the 3 (-5) loculi of the ovary. The fruit is a “drupe” with 1–3 (-5) stones. The inflorescence is made up of cymes grouped in an umbel-like arrangement.

Sambucus (Elder, Fig. 592) has imparipinnate leaves and a “drupe” with 3 (-5) stones. Between the calyx and the style a disc remains on the apex of the fruit. S. nigra with black fruit; S. racemosa with red fruit; S. ebulus is a perennial herb; the others are woody.--Viburnum (Guelder-rose) has simple leaves (penninerved or palminerved, entire, dentate or lobed), and a “drupe” with only 1 stone, which is compressed, cartilaginous, and parchment-like; 2 of the loculi of the ovary are aborted. ~(In V. opulus the marginal flowers of the inflorescence are barren, and in that case their corollas are generally specially large; the cultivated Viburnum has only barren flowers, with large corollas.)~

=3.= LINNÆEÆ. Linnæa borealis (the only species) is an extreme form of the order; it has a 2-flowered dichasium, funnel-shaped, slightly bilabiate corollas (2/3); 4 didynamous stamens. Two of the 3 loculi of the ovary have several ovules which are not developed, while the third has only 1 ovule, which developes into a seed. The fruit is a nut, which is enveloped by the two large bracteoles, which are covered by sticky, glandular hairs, and serve as a means of distribution. It is a small undershrub.

[Adoxa, which was formerly classed in this order, appears, according to recent investigations, to be more properly placed among the Saxifraginæ.]

In cases where the flowers are small, as in Sambucus and Viburnum opulus, they are rendered conspicuous by being arranged in closely-packed inflorescences; they are massed together and form large surfaces, and in the last named are still more conspicuous on account of the barren, but large ray-flowers, which are of service in this respect. Honey is secreted in the nectaries at the base of the styles. In the genera with rotate flowers, as Viburnum and other Sambuceæ, the honey lies so exposed and in such a thin layer, that only flies and insects with short probosces can procure it; bees, however, visit these flowers for the sake of the pollen. There is hardly any nectar in the Elder; self-pollination frequently takes place. The flowers of the Caprifoliaceæ, which, with their long corolla-tube are adapted for evening-and night-flying insects with long probosces, open in the evening, and at that time give off their strongest scent.

DISTRIBUTION. 230 species; especially outside the Tropics in the Northern Hemisphere. In this country they are found especially in hedges and as under-shrubs.--OFFICINAL: the flowers and fresh fruits of the Elder (S. nigra), the fruits (“berries”) being also used in the household. ORNAMENTAL SHRUBS: species of Lonicera, Symphoricarpus, Diervilla, which are chiefly from N. Am., Abelia and Viburnum.

Family 34. =Dipsacales.=

The leaves are opposite and without stipules. The flower (Figs. 593, 595, 598, 599, 600) is epigynous, zygomorphic or asymmetrical, 5-merous with S5, P5, stamens typically 5, but by suppression never more than 4, sometimes less, carpels 3–2. The calyx is more or less insignificant, and almost suppressed in the extreme forms. The ovary has 3–1 loculi, but only one loculus has an ovule, which is pendulous with the micropyle turned upwards (Fig. 594). Fruit a nut. Embryo straight, with the radicle pointing upwards (Fig. 597), without or with endosperm.

The inflorescences are distinct dichasia in Valerianaceæ, but in Dipsacaceæ and Calyceraceæ they are crowded together into capitula.

This family is closely allied to the Rubiales through the Valerianaceæ, which have almost the same structure as many of the Caprifoliaceæ. It attains the highest development in the Dipsacaceæ, which are composite plants, but differs from Compositæ in the position of the ovule, etc.

Order 1. =Valerianaceæ.= Herbaceous plants or under-shrubs with opposite leaves, often pinnate; stipules absent. The flowers are borne in dichasia and in scorpioid cymose inflorescences and are entirely without any plane of symmetry (Fig. 593). The calyx and corolla are 5-merous, but the calyx is frequently very insignificant and ultimately a pappus, as in Compositæ; the corolla is frequently saccate or produced into a spur at the base. Most frequently, only 3 (4–1) of the 5 stamens are developed; these are free. Carpels =3=, which form an inferior ovary, often with 3 loculi, but only 1 of the loculi contains =1= pendulous, anatropous ovule (Figs. 593, 594 A), the other loculi are empty and shrink up more or less completely. (Compare Fig. 593 A, B). Style 1, stigma tripartite. Endosperm absent; embryo straight, with the radicle directed upwards.

The inflorescences are dichasia, or unipared scorpioid cymes with the branches developed in the axil of the second bracteole. Both the bracteoles are generally present and frequently form 4 very regular, longitudinal rows on the branches of the inflorescence.--5 stamens do not occur (except perhaps in Patrinia). The suppression of stamens and carpels takes place most readily on the anterior side of the flower and that turned towards the first bracteole (a) (Fig. 593), whose branch is suppressed in the dichasium; after this the posterior median stamen is next suppressed.

By the vegetative characters as well as by the inflorescence and the flower, the order is allied to the Caprifoliaceæ and especially to the Sambuceæ.

In the least modified (oldest) forms, Patrinia and Nardostachys, there is an almost regular flower, a 5-merous calyx, 4 stamens, and 3 loculi in the ovary, 2 of which however are barren. The stamens in Valerianella are reduced to 3, in Fedia to 2 (posterior), and the calyx is less distinctly 5-dentate; the 2 empty loculi in the ovary are still visible. Fedia has a small spur at the base of the corolla. Valeriana has a very reduced, hair-like calyx (pappus), an unsymmetrical, salver-shaped corolla with a sac-like, nectariferous spur at the base, 3 stamens and only 1 loculus in the ovary (Figs. 594, 593). Centranthus (Fig. 593) is still further reduced. The corolla has a spur and only 1 stamen; ~unipared scorpioid cymes with 4 rows of bracteoles. In the last two genera there is a peculiar wall in the corolla-tube, which divides it longitudinally into two compartments (indicated by a dotted line in Fig. 593), one of which encloses the style. This wall is low in Valeriana, but in Centranthus it reaches as far as the throat.--The rays of the pappus are pinnately branched and rolled up before the ripening of the fruit. 12–20 in number (Fig. 594 A, B).~

Val. officinalis and others are protandrous: in the first period the stamens project from the centre of the flower (Fig. 595 a), the stigmas in the second (b) when the stamens have become bent backwards. (V. dioica is diœcious with large ♂-and small ♀-flowers).--275 species; especially from the temperate and colder parts of the northern hemisphere of the Old World, Western North America and the Andes.--Bitter properties are characteristic, such for instance as the volatile acid and volatile oil of Valeriana; these occur especially in the rhizomes. OFFICINAL; the rhizomes of V. officinalis.--The true Indian “Nardus,” an important medicine and perfume in India, is extracted from Nardostachys (Himalaya). A variety of Valerianella olitoria is sometimes used as salad.

Order 2. =Dipsacaceæ= (=Teasels=). Herbs with opposite leaves without stipules. The flowers are situated in compact capitula each with an involucre. A characteristic feature of the order is that each flower of the capitulum has a gamophyllous “epicalyx” (Figs. 597, 599, 600), which envelopes the inferior ovary. The flowers (Figs. 599, 600) are ☿, 5-merous (S5, P5, stamens typically 5, G=2=), but the calyx often expands at the edge into a membrane with 5, or an indefinite number of bristles or teeth (pappus, Figs. 597, 600), and the zygomorphic, funnel-shaped corolla is sometimes 5-lobed and bilabiate (2/3), but most frequently 4-partite (Fig. 599), the two lobes of the upper lip coalescing into one lobe, as in certain Labiatæ, Veronica and Plantago; the æstivation is imbricate.

The stamens are never more than 4, the posterior one remaining undeveloped; they usually have free anthers which generally project considerably (Fig. 599). The ovary is unilocular with 1 pendulous ovule and bears 1 undivided style; fruit a nut with 1 seed, containing endosperm and with the radicle turned upwards (Fig. 597).

The flowers do not always open in centripetal order, a fact which may be observed especially in the Dipsacaceæ, in which a zone of flowers round the centre of the capitulum opens first, and the flowering then proceeds both upwards and downwards (Fig. 598). This has probably some connection with the fact that the capitulum has arisen from the coalescence of several dichasial inflorescences. In species of Scabiosa the flowers open simultaneously at the circumference, or in a zone at the centre.--The morphological explanation of the “epicalyx” is not quite certain; in all probability it is formed from two united bracteoles, for an “epicalyx” is distinctly formed in this way in one of the Valerianaceæ, Phyllactis.--The ray-flowers are larger and more irregular, labiate or ligulate, than the disc-flowers, yet not in so high a degree as in the Compositæ.

=A.= A scarious bract to each flower. Scabiosa has a 5-lobed corolla; the “epicalyx” has a dry, scarious, often finally large collar, and the true calyx is formed of long bristles (generally 5) (Fig. 597). Succisa pratensis (Devil’s-bit) has a 4-lobed corolla, the collar of the “epicalyx” is herbaceous; the calyx as in the preceding.--Pterocephalus.--Dipsacus (Teasel); large, spiny and stiff-haired herbs with capitula, or short, thick spikes on which both the involucral-leaves and bracts project considerably, and are stiff and spinose (Fig. 598). The “epicalyx” has short teeth, or is almost entire. ~The leaves of the stem unite together in pairs, so that shallow cups are formed round the stems in which rain-water may collect.--Cephalaria.--Morina: the flowers are falsely verticillate as in the Labiatæ; the calyx has 2 laterally-placed, entire, or emarginate lobes; 2 stamens, or 2 large and 2 small ones.~

=B.= Bristles, but no true bract to each flower. Knautia; the corolla is 4-partite, the calyx cup-like, with many bristles or teeth on the edge.

POLLINATION is in many species effected by insects. The honey is secreted by a ring round the base of the style. The flowers in our native species are considerably protandrous. Gynodiœcious flowers also occur.--150 species; especially in the Mediterranean and the Orient; the order is not represented in the South Sea Islands, Australia and America.--The heads of the true Teasel (Dips. fullonum) are used for carding wool, on account of the elastic bracts, which are hooked at the point. The order has bitter properties; tanin, etc.; but no species are used in medicine or the household.--Scabiosa atropurpurea, etc., are used as ornamental plants.

Order 3. =Calyceraceæ.= This order resembles the Compositæ in the valvate æstivation of the corolla and the more or less united stamens, and the Dipsacaceæ in the undivided style, pendulous ovule and endosperm. The calyx is frequently composed of 5 distinct scales. An “epicalyx” is wanting.--20 species; America.

Family 35. =Campanulinæ.=

The flower is epigynous, perfect, with 5 sepals, 5 petals, and 5 stamens in regular alternation, and =3= (2–5) carpels. The sepals in all cases are distinct, but narrow and pointed, so that the æstivation is open. The corolla is gamopetalous with (as in the Compositæ) valvate, or slightly infolded-valvate æstivation. The stamens are nearly always situated on the torus without being united to the corolla (Figs. 601, 604). The anthers adhere or unite and form a tube with introrse anthers from which the pollen is swept out by the projecting, brush-like hairs on the style (as in the Compositæ). The ovary is =3=-(2–5) locular, many ovules in each loculus. The fruit is generally a many-seeded capsule (or berry). Embryo in the centre of a fleshy endosperm.--The majority are herbs with scattered leaves, without stipules. The presence of latex and inulin, together with the tubular formation of the anthers, the pollination, etc., indicate a relationship with the Compositæ.

The Cucurbitaceæ are by some authorities placed in this family as being most closely related to the Campanulaceæ. Although the corolla is most frequently gamopetalous, and other similarities to the Campanulaceæ are present, yet on account of the structure of the ovule, and for other reasons, the Cucurbitaceæ are here placed in the Choripetalæ. The Campanulinæ without doubt proceed upwards to the Compositæ, with which, in addition to the occurrence of inulin and laticiferous vessels (Cichorieæ), there are many corresponding features both in the structural and biological relations (epigyny, valvate æstivation of the corolla, tendency of the anthers to adhere or unite, protandry with a stylar-brush, etc.) The inflorescence of Jasione is almost identical with that of the Compositæ.

Order 1. =Campanulaceæ= (=Campanulas=). The flowers are regular and in some only semi-epigynous, 5-merous, except in the gynœceum which is 3-merous (the unpaired, median carpel being generally posterior), more rarely 2–5-merous, and has a corresponding number of stigmas and loculi in the ovary; the placentation is axile with a large number of ovules. The median sepal is posterior. The stamens frequently have broad, free bases (Fig. 601 H) which cover the nectariferous upper surface of the ovary; the anthers only fit loosely together, and become separated as soon, as the pollen is shed (Fig. 601 G), 1 long style, which is studded by sweeping-hairs (stylar-brush), which ultimately become invaginated; the stigmas do not unfold until the stamens have shed the pollen (Fig. 601 E, G). Fruit a capsule.--Herbs, more rarely under-shrubs or shrubs, with latex and scattered, undivided leaves without stipules. The inflorescence is most frequently a raceme or spike with terminal flower.

=A.= Capsule opening at the side by pores and small valves: Campanula (Canterbury-bell); the corolla is bell-shaped, rarely almost rotate; capsule obconical. ~The pores of the capsule are found near the top of the fruit when it is erect, and near the base when it is pendulous, so that the seeds are not liberated unless the capsule is forcibly shaken, and they are thus ejected to a considerable distance.~--Phyteuma (Rampion) has free petals, which for a long time adhere at the apex and form a tube round the stamens (Fig. 601); inflorescence compact, spike-like or capitate, in the latter case resembling that of the Compositæ, and frequently with an involucre similar to the one possessed by this order. ~Specularia (rotate corolla, prismatic capsule), Michauxia (flower 8-merous).--Symphyandra has syngenesious anthers.~

=B.= Capsule with valves at the apex, loculicidal dehiscence: Jasione; the petals are almost free. The anthers are united at the base (syngenesious). The flowers are situated in capitate umbels with involucres.--Wahlenbergia; Platycodon.

=C.= Berry: Canarina; flower, 6-merous; leaves opposite.

Protandry is general (Fig. 601). 510 species; principally in temperate countries. Several genera furnish ornamental plants, but are of little use for other purposes. The roots of some Campanula-and Phyteuma-species are large and may serve as pot-herbs (C. rapunculus, P. spicatum).

Order 2. =Cyphiaceæ.= In this order the corolla is zygomorphic and the stamens free, hence it is intermediate between orders 1 and 3.--About 24 species; Africa.

Order 3. =Lobeliaceæ= (=Lobelias=). This order may briefly be described as Campanulaceæ with zygomorphic flowers and anthers united into a tube, in most cases slightly bent; generally 2 carpels and an inverted position of the flower, i.e. the median sepal is turned anteriorly (Fig. 602) (a position which is found to occur within the Campanulaceæ). A twisting of the peduncle takes place even before flowering (as in the Orchids) so that the ordinary position of the 5-merous Dicotyledons appears to be restored. The zygomorphy of the flower is especially present in the corolla, which has a bipartite under-lip and a tripartite upper-lip, and is, in Lobelia, anteriorly (apparently posteriorly) deeply cleft (Fig. 602). There is 1 style, but the stigma is capitate and bilobed and surrounded at its base by a whorl of hairs, which assists in pollination (as a stylar-brush) in the same manner as the sweeping-hairs in the Campanulaceæ and Compositæ. There is no terminal flower in the spicate, or racemose inflorescences.--Lobelia has a capsule, several others have berries. ~Isotoma (regular flower); Heterotoma has a spur; Siphocampylos; Lysipoma (pyxidium); Clintonia (1–locular fruit). Metzleria (all the petals are free).~

Entomophilous and protandrous. About 500 species, especially in the Tropics; in this country, L. dortmanna (margin of lakes).--Several are cultivated in gardens and conservatories as ornamental plants (Lobelia bicolor, erinus, fulgens, etc., Siphocampylos, Centropogon). The latex of several species of Tupa is poisonous; caoutchouc is also obtained from them. OFFICINAL: “herba Lobeliæ” (the alkaloid lobeline) from the poisonous L. inflata (N. Am.).

Order 4. =Goodeniaceæ.= Chiefly Australian (200 species), closely related to Orders 3 and 5, but without latex. The style is provided with a “collecting-cup” which receives the pollen before the flower opens; it has a small, hairy aperture through which the pollen is forced out by the stigmas, and through which they emerge when the pollen is shed; it is sensitive and exhibits movements when touched.--Herbs, under-shrubs, less frequently shrubs. Goodenia, Leschenaultia, Scævola.

Order 5. =Stylidiaceæ= (or =Candolleaceæ=); 100 species, the majority Australian; zygomorpbic flowers, but with the ordinary position. The anterior petal is very small. The chief characteristic feature is the presence of only 2 stamens (with extrorse anthers) which are united with the style and form a stylar-column; this is bent like a knee and sensitive at the bend to such a degree that when touched it jerks violently across the flower to the opposite side and then loses its sensitiveness.--Herbs, less frequently under-shrubs. Stylidium (Candollea).

Family 36. =Aggregatæ.=

The flowers, which are borne in “capitula” (Figs. 605, 610), are epigynous (Fig. 605 C, D), 5-merous in the calyx, corolla and andrœcium, the corolla is valvate in æstivation, with =2= carpels (S5, P5, A5, G2). The anthers are united into a tube (syngenesious) (except Ambrosieæ) which surrounds the bifid style. There is never more than =1= loculus in the ovary, with =1= erect, anatropous ovule. The fruit is a 1–seeded nut (cypsela), with thin pericarp, the calyx generally persists as a tuft of hairs (pappus) (Fig. 606) on the summit of the fruit. Embryo without endosperm; the radicle directed downwards.

Only 1 Order: Compositæ.

With respect to the inflorescence and the development of the individual flowers, there is a very close resemblance to the Dipsacaceæ, which stand on the same plane of progression as the Compositæ. But while the latter are allied to Campanulinæ as the last stage in the process of evolution, the Dipsacaceæ form the final stage of the Rubiales-Dipsacales.

Order =Compositæ=. (For the principal characteristics compare those of the family.) The Compositæ are chiefly herbs, but trees and shrubs also occur in tropical countries. The leaves may be scattered or opposite, but have no stipules. The outer leaves of the involucre as a rule are barren, especially when numerous and imbricate, while the innermost ones support the ray-flowers of the capitulum; in a few instances all are fertile (e.g. Tragopogon, Tagetes). The CAPITULA are many-flowered, with the exception, e.g. of Echinops, which has 1-flowered capitula (see page 570). The capitula are again arranged in inflorescences, most frequently corymbose with centrifugal order of development. The form of the receptacle is an important character for the division of the genera (flat, convex, conical), and also the presence of scales; these may be one scale (bract) for each flower (Fig. 610 br), or a large number of bristles, which do not each correspond to a leaf, or the receptacle may be entirely without covering (naked). The flowers open in acropetal order in each capitulum. All the flowers in a capitulum may be of the same sex, and their form and colour are in that case the same, or the sexes may be different, in which case the form and colour are also most frequently different: the ray-flowers have projecting labiate or ligulate corollas, while the disc-flowers have tubular corollas. As a rule in the latter case the ♀ flowers are at the circumference, and the ☿ in the centre, less frequently ♀-flowers at the edge and ♂-flowers in the centre. The ray-flowers in some genera are neuter (e.g. Centaurea). Some are diœcious.

There is no trace of an epicalyx (in contrast to the Dipsacaceæ, which they generally so resemble). The formation of the CALYX is very varied. The calyx always consists of a very small cushion-like structure, most frequently developed later than the corolla; the 5 corners, which correspond to the 5 sepals, in a few instances are raised as 5 large, flat, membranous bodies, e.g. in species of Xeranthemum, Catananche, Sphenogyne, etc.; in other instances each of these bears a shorter or longer bristle on its apex, followed by others in rather uncertain numbers and with but slight indications of order, on the edge and on the outer side of the calyx between the 5 points; in other instances, again, the calyx is covered with bristles and hairs without any indication of order or definite number (Fig. 606 a, b); finally instances occur in which the edge is raised as a membranous collar, irregularly toothed and notched, or divided into small scales. There are naturally differences in the means of distribution corresponding to the differences in structure of the calyx. The fruits a and b represented in Fig. 606 are distributed by the wind, those like c, on the other hand, by attaching themselves to animals and human beings. The rays of the pappus are termed rough when special cells project a little beyond the surface, but if these grow out, and are hair-like, the pappus is said to be feathery. In some genera the pappus is raised on a long stalk, which is developed from the upper part of the fruit, and termed a beak (Fig. 606 a). The pappus does not attain its full development till the ripening of the fruit, i.e. until it is about to be of use.

The COROLLA has various forms: (a) tubular (Fig. 605 D), with a shorter or longer tube, not always of the same bore throughout and especially slightly widened at the top to form a bell-shaped opening, with 5 regular teeth: (b) labiate after 2/3, i.e. with 2 petals in the upper and 3 in the under lip: (c) ligulate, i.e. the corolla is split for a considerable distance on the posterior side (as in the Labiate genus Teucrium) and prolonged into a long, strap-like portion (Fig. 609 A), which projects upwards. A distinction must, however, be drawn between the true and false ligulate corolla. In the first case the corolla has 5 teeth at the apex (Fig. 609 A) and is made up of all the petals of the corolla united together; this is the usual condition in the Ligulate-flowered. In the latter case (Fig. 605 C) the tongue has only 3 teeth (or is more irregularly 2–3-dentate), and is only formed of 3 petals; the corolla is then truly bilabiate, the tongue is the large under lip, and the upper lip is very slightly developed, or even at an early stage quite suppressed. This false “ligulate” corolla is found among the ray-flowers; sometimes the upper lip is seen quite plainly, e.g. in Tagetes, especially in the double capitula. ~The VENATION of the corolla is peculiar; there are always commisural veins which branch dichotomously at the angles between the teeth of the corolla, and send a branch into the edge of the two nearest teeth. The midrib is frequently absent, but may be present, and then it has sometimes no connection with the other veins of the corolla.~

The STAMENS are attached to the corolla, and have free filaments (Silybum has united filaments), but the anthers, which at first are free, adhere together and form a tube (Fig. 605 E: only Ambrosieæ have free anthers). The connective is generally prolonged, and protrudes above the anthers as a thin, brown membrane of various forms (Fig. 605 E); appendages of various forms may also be found at the base of the anthers. The anthers open introrsely, and the pollen must be carried out at the top of the tube by upward growth of the style, and by means of the “stylar-brush” (Figs. 607, 608, 609); the filaments are sometimes sensitive (e.g. in the Corn-flower, Fig. 607), and shorten on being touched, so that the anther-tube is pulled downwards, and the pollen swept out at the top (Figs. 607, 608 A, B).

The STYLE divides at the apex into two branches (Figs. 609, 610), both of which generally bear on the inner surface two lines of stigmatic papillæ (Fig. 610 B, C) and being in shape, etc., very varied, are therefore employed as systematic characters.--~The most important types are: =A.= The style is uniformly cylindrical; its branches are semi-cylindrical, long, and with long hairs, and finally bend backwards; the stylar branches bear slightly projecting stigmatic papillæ on the inner side. This form is characteristic of the Cichorieæ (Fig. 609 A B). =B.= The style is uniformly cylindrical; the branches are long, cylindrical or club-like, short, not rolled back, with fine hairs externally; the stigmatic lines do not reach beyond the centre, and do not meet together. Characteristic of Eupatorium, Petasites, Tussilago. =C.= The style is thickened beneath the stigmatic branches in the form of a knob, or very hairy (Fig. 609 C); the stigmatic lines reach as far as the apex of the branches and then converge; sometimes the stigmatic branches are united as far as the apex. Characteristic of the Cynareæ. =D.= The stylar branches are lanceolate, or linear, pointed; externally flat and thickly covered with hairs in the upper portion; the stigmatic lines cease where the hairs commence externally. Characteristic of Aster, Bellis, Inula, Dahlia, etc. =E.= The stylar branches are linear, with long, brush-like hairs at the apex, where they are either abruptly cut off or prolonged into a very hairy, conical appendage; the stigmatic lines are broad, reach as far as the brush-like hairs, and do not meet together (Fig. 610). Characteristic of Senecio, Helianthus, Xanthium, Gnaphalium, Artemisia, Anthemis, and others related to these.~

A ring-like nectary is found round the base of the style.

The thin-walled cypsela (Fig. 606), with seeds fitting closely to the pericarp, has many different forms (smooth, ribbed, spined, etc.); its point of attachment generally lies at the lowest end but sometimes it is drawn obliquely up the side (Centaurea, etc.). The calyx, persistent on the apex of the fruit, has been described above. Some genera have two or three different forms of fruits in each capitulum.--The embryo is straight, with the radicle turned downwards, and without endosperm, but is rich in oil.

The variously flowered capitula, whose normal tubular disc-flowers have been changed to ligulate flowers, may be termed “double flowers.”

The relationship of the Compositæ to the Campanulinæ has been described above (page 561). The alliance with the Dipsacaceæ is more apparent than real. Similar capitate inflorescences also occur as the final stage in other lines of descent, as in Eryngium among the Umbelliferæ.

=1. Cynareæ, Thistle Group.= Flowers all ☿, regular, with tubular corollas. The receptacle is covered with numerous bristles, which surround the flowers without any definite order, or the edges of the grooves in which these are placed have a well-marked fringe. The involucral leaves are numerous, imbricate, and are either prolonged into a thorn or terminate with a membranous edge. The style has been described on page 568 (Fig. 609 C). Nearly all have a hairy or feathery pappus. The filaments are sensitive.

Carduus (Thistle); capitula ovoid; involucral leaves compact, imbricate, with thorny points; the pappus-rays are hair-like and united at the base by a ring (i.e. the calyx), and fall off together.--Cirsium (Fig. 608) has a feathery pappus, in other respects it is like Carduus. ~C. arvense reproduces and passes the winter by means of suckers.~--Cynara (Artichoke) has a feathery pappus and large, solitary capitulum, with broad involucral leaves; these have a fleshy base like the receptacle (edible).--~Silylum has united filaments. S. marianum (Milk-thistle), has leaves with numerous white spots. Onopordon (Cotton-thistle). Cnicus (C. benedictus) has a large, many-spined thorn on the involucral leaves; pappus trimorphic.~--Lappa (Burdock) is easily recognized by the hooked involucral leaves, which assist in the distribution of the fruit; in this respect it differs from the other inflorescences, and also in the fact that the pappus is short, and quickly falls off, without serving as a means of distribution.--~Carlina; the external involucral leaves are leafy, thorny, with branched or unbranched spines standing straight out or bent backwards; the internal ones are dry, and prolonged as dry, coloured, radiating scales. The well-developed bristles on the receptacle and edge of the calyx are deeply cleft and lobed.~--Centaurea (Knap-weed, Fig. 607). The ray-flowers are neuter, and generally larger than the disc-flowers; the involucral leaves are regularly imbricate, but are frequently provided at the apex with a dry, chaffy, often lobed, fringed appendage. The attachment of the fruit is lateral. Serratula (Saw-wort).--~Carthamus, the outer and inner involucral leaves differ very much.~--Echinops (Globe-thistle) is characterised by having “compound capitula,” i.e. there is only one flower in each capitulum, but many such capitula are collected into a spherical head, which at the base may also have a few involucral leaves. The individual capitula have narrow, linear involucral leaves. ~(There are altogether about 150 species of Compositæ with 1-flowered capitula, all from warm countries.)~--Xeranthemum, Staehelina, Jurinea, Saussurea, etc.

=2. Mutisieæ, Labiate-flowered Group.= Tropical (S. American) forms whose zygomorphic flowers have a bilabiate corolla (2/3). The involucre is nearly the same as in the Thistles.

=3. Cichorieæ, Chicory Group= (or LIGULIFLORÆ). The flowers are all ☿ and have a ligulate, 5-dentate corolla. The stylar branches are thin and prolonged (Fig. 609 B). Laticiferous vessels occur in the majority (in this feature they resemble the Lobeliaceæ and Campanulaceæ).

=A.= The pappus is wanting, or it is scale-like, but not long and hairy.--Cichorium (Chicory); capitula with blue flowers, borne singly or a few together in the leaf-axil; there are two whorls of involucral leaves, an outer one of short and radiating, an inner of more numerous, longer and erect leaves; pappus, scale-like.--Lapsana (Nipplewort). The few involucral leaves are nearly of the same size, and persist forming a sort of capsule round the fruits, which are entirely without a pappus. There are only a few flowers in the small capitula.--Arnoseris (Swine’s-succory), Catananche, etc.

=B.= The pappus is long and hairy (not branched), generally fine and snowy-white. There are no scales on the receptacle. The two genera first considered have beaked fruits.--Taraxacum (Dandelion) (Fig. 606 a); the capitula are many-flowered, and borne singly on the top of a leafless, hollow stalk.--Lactuca (Lettuce) has many small, few-flowered capitula borne in panicles.--Crepis (Hawksbeard).--Hieracium (Hawk-weed) has many imbricate involucral leaves, and a stiff, brittle, brownish pappus.--Sonchus (Sow-thistle); the capitula, when a little old, have a broad base, and are abstricted above in the form of a jug; involucral leaves imbricate; the fruit is compressed, without a beak, ridged. The soft, white pappus falls off collectively.

=C.= The pappus is feathery and branched; no scales on the receptacle.--Tragopogon (Goat’s-beard) generally has 8 involucral leaves in one whorl. The fruit has a long beak; the rays of the pappus are interwoven in the form of an umbrella.--Scorzonera has fruits like the preceding, but almost without any beak; involucral leaves many, imbricate.--Leontodon (Hawkbit) has a slightly feathery pappus, rays not interwoven; beak absent.--Picris.

=D.= Long, chaff-like, deciduous scales on the receptacle; pappus feathery.--Hypochœris (Cat’s-ear).

=4. Eupatorieæ, Hemp-agrimony Group.= All the flowers are most frequently ☿; corollas tubular and regular; the involucral leaves are not stiff and spiny; the receptacle is not covered with stiff bristles. The stylar branches are long, club-like, or gradually tapering. There is no swelling below the stigma.

Eupatorium (Hemp-agrimony); all the flowers are ☿.--Petasites (Butterbur); ray-flowers ♀, disc-flowers ☿ or ♂; sometimes diœcious. Capitula in racemes or panicles. The leaves develop after the flowering.--Tussilago (T. farfara, Colt’s-foot) has a solitary capitulum borne on a scaly, scape-like stem; the ray-flowers are ♀ with ligulate corollas, disc-flowers ♂. The leaves unfold after the flowering. Ageratum, Mikania, Vernonia.

=5. Astereæ, Aster Group= (or RADIATÆ, Ray-flowered). The flowers are of two forms and different sexes; the ray-flowers are ♀ (sometimes neuter), most frequently with irregular, falsely ligulate, radiating corollas; the disc-flowers are ☿, regular, with tubular corollas (Fig. 610). Sometimes only tubular flowers are present, as e.g. in Senecio vulgaris (Groundsel), and the exterior of the capitulum is then as in the Eupatorieæ. The stylar branches are straight, more or less flat and short (Fig. 610).

=A.= ANTHEMIDEÆ. Involucral leaves imbricate, generally membranous at the edge; pappus wanting, or at most a membranous margin to the calyx, but without hairs.

[+]. Chaff-like bracts on the receptacle are found in Anthemis (Chamomile), Anacyclus (A. officinarum), Achillea (Milfoil, Fig. 610), Santolina, etc.

[++]. A naked receptacle is found in the following: Bellis (Daisy) has solitary capitula on leafless stalks with white ray-flowers.--Matricaria (Wild Chamomile) has a conical receptacle. ~(M. chamomilla has a very high, hollow receptacle; M. inodora has large, odourless capitula, and the receptacle is not hollow.)~--Chrysanthemum (Ox-eye) most frequently large, solitary capitula; flat receptacle.--Pyrethrum; pappus scanty.--With these are classed Tanacetum (Tansy) and Artemisia (Wormwood) with tubular corollas only.

=B.= HELIANTHEÆ. Most frequently a bract to each flower is found on the receptacle. The pappus is never exactly hairy, but consists of scales, spines, etc., and the fruits are most frequently compressed (Fig. 606 c).--Helianthus (Sun-flower); H. tuberosus (Jerusalem Artichoke) has tuberous underground stems. Dahlia has tuberous roots (Am.). Bidens (Bur-marigold, Fig. 606 c); the fruits are compressed with 2 (or more) spines provided with reflexed barbs.--Calliopsis; Rudbeckia; Zinnia; Tagetes has united involucral leaves, and yellow, transparent oil-glands. Spilanthes, Galinsoga, Melampodium, Silphium (Compass-plant), Helenium, Gaillardia.

=C.= CALENDULEÆ have 1–2 rows of involucral leaves, a naked receptacle, and large, crescent-shaped, irregularly warted fruits, of different forms in the same capitulum; pappus absent (Fig. 605).--Calendula (Marigold); ray-flowers ♀, disc-flowers ♂.

=D.= SENECIONEÆ, have a fine, hairy, white pappus; no bracts, otherwise as in Anthemideæ. The involucral leaves are most frequently in 1–2 rows.--Senecio (Groundsel) has two whorls of involucral leaves, which most frequently have black tips, the external being much shorter than the internal ones (S. vulgaris has all flowers ☿ and alike).--Cacalia, Doronicum, Cineraria, Ligularia, Arnica (A. montana; large, long-stalked capitula; leaves opposite, forming a kind of rosette).

=E.= ASTEREÆ have a bristle-like, unbranched pappus, often of a dingy brown; receptacle naked; involucral leaves numerous, imbricate.--Solidago (Golden-rod); capitula small, yellow-flowered, borne in panicles. Aster; disc-flowers most frequently yellow, ray-flowers violet; Callistephus; Erigeron (Flea-bane)--Inula.--All the corollas are tubular in: Gnaphalium (Cud-weed); involucral leaves dry, rattling, often coloured; the foliage-leaves and stem often white with woolly hairs; ray-flowers ♀, with narrow, tubular corolla; disc-flowers ☿ (few). Antennaria (Cat’s-foot; diœcious), Filago, Helichrysum, Ammobium, Rhodanthe and others. Leontopodium (L. alpinum, “Edelweiss”).

=F.= AMBROSIEÆ, a very reduced type of Compositæ, differing from the others in having free anthers; the capitula are generally unisexual, monœcious, the ♂ borne in a terminal inflorescence, the ♀ in the leaf-axils. In other respects they are most closely related to Heliantheæ.--Xanthium. In the ♂-capitula there are many flowers without calyx, but with tubular corolla and free involucral leaves. In the ♀-capitula there are only 2 flowers, which are entirely destitute of both calyx and corolla; involucral leaves 2-spined, united to form an ovoid, bilocular envelope, each compartment containing one flower. The envelope of involucral leaves unites with the fruits, enclosing them at maturity with a hard covering from which numerous hook-like spines project, assisting very greatly in the distribution of the fruit. The whole structure thus finally becomes a 1- or 2-seeded false nut.--Ambrosia, the ♀ capitulum 1-flowered.

POLLINATION. The flowers are somewhat insignificant, but become very conspicuous owing to a number being crowded together in one inflorescence. The corollas of the ray-flowers, being often very large (Astereæ; Centaurea), frequently render the capitula still more conspicuous. The capitula display many biological phenomena similar to those often shown by the individual flowers in other orders, e.g. by periodically opening and closing, in which the involucral leaves resemble the calyx in their action. (The name “Compositæ” originates from the term “flos compositus,” composite flower). An abundance of honey is formed, which to some extent fills up the corolla-tube, and since insects may visit a number of flowers in the course of a short period they are very frequently visited, especially by butterflies and bees. The pollination has been described on page 567. Protandry is universal. In the bud the tips of the styles, covered by the sweeping-hairs, lie closely enveloped by the anther-tube; in the next stage the style grows through the tube and sweeps out the pollen as it proceeds; ultimately the stylar branches expand and the stigma is then prepared to receive the pollen. In many, the sensitiveness of the filaments assists in sweeping out the pollen at the exact moment of the insect visit. Regular self-pollination is found e.g. in Senecio vulgaris; wind-pollination e.g. in Artemisia and the plants related to it.

This extremely natural and well-defined order is the largest (and no doubt one of the youngest?); it embraces 10–12,000 known species (in 770 genera), or about one-tenth of all Flowering-plants. They are distributed over the whole globe, but are most numerous in temperate countries; the majority prefer open spaces; a smaller number are forest-forms. They abound especially in open districts in America.

Among the substances frequently found may be mentioned: INULIN (especially in the subterranean parts), BITTER materials, Tannin, volatile oils, fatty oils in the fruits. MEDICINAL:[40] “Herba” of Artemisia absinthium (Wormwood) and maritima[+] (Sea-wormwood), Achillea millefolium; the leaves of Cnicus benedictus and Tussilago farfara; the unopened capitula of Artemisia maritima, var. stechmanniana; the capitula of Tanacetum, Matricaria chamomilla[+] (wild Chamomile), Anthemis nobilis[+] (common Chamomile); the separate flowers of Arnica; the roots of Arnica montana[+], Taraxacum officinale[+], Anacyclus officinarum[+], Lappa major, minor, nemorosa and tomentosa, Inula helenium and Artemisia vulgaris; the latex of Lactuca virosa[+]. The following are cultivated for food:--Lactuca sativa (Lettuce), Cichorium endivia (from E. Asia, for salads), Cynara scolymus (Artichoke, Mediterranean), Scorzonera hispanica (S. Eur.), Helianthus tuberosus (Jerusalem Artichoke, from N. Am., introduced into Europe 1616), Cichorium intybus (roots as “chicory,”) Tragopogon porrifolium (Salsafy), Artemisia dracunculus. OIL is extracted from the following (the seeds): Helianthus annuus (Peru), Madia sativa (Chili), Guizotia oleifera (Abyssinia). DYES from: Carthamus tinctorius (Safflower, used in the preparation of rouge; Egypt), Serratula tinctoria. INSECT-POWDER from: Pyrethrum cinerariifolium (Dalmatia) and roseum (Persia, Caucasus). The following are cultivated in houses and gardens for the sake of their scented leaves:--Tanacetum balsamita (Balsam), Artemisia abrotanum (Southernwood) and A. argentea. A great many of the genera enumerated are cultivated in dwelling-houses for the sake of the flowers; e.g. Pericallis cruenta (generally termed “Cineraria”). Asteriscus pygmæus is supposed to be the genuine “Rose of Jericho”; the involucral leaves envelop the fruits after their ripening and keep them enclosed for 8–10 months until rain occurs.

APPENDIX ON THE CLASSIFICATION OF PLANTS.

BY M. C. POTTER.

The earliest systems of classification were derived from the properties and uses of plants; and it was not until some two centuries ago that any scientific grouping of plants was attempted. Aristotle and Theophrastus had adopted the groups of Trees, Shrubs and Herbs as the chief divisions of the Vegetable Kingdom, a system which persisted and was employed by Tournefort and Ray as late as the end of the 17th century. The arrangement by which these three divisions were separated into smaller divisions was often founded upon a single character, such as the formation of the corolla, the form of fruit, that of the calyx and corolla, etc. All these systems of classification which brought into close proximity plants distinguished by some one character alone, could only be considered as artificial, since plants related to one another would not necessarily be included in the same group. As the knowledge of the morphology, physiology, and reproduction of plants increased, such systems were recognised as unscientific, and it became the aim of botanists to establish a natural system, founded upon mutual relationships, which would associate together only those plants which are truly allied.

The following are some of the chief systems of classification which will show the gradual development of the natural system, and may be of service to students making use of this text-book.[41]

System of JOHN RAY (1703).

I. Herbæ. A. IMPERFECTÆ (Flowerless). B. PERFECTÆ (Flowering). Dicotyledones. Monocotyledones. II. Arbores. A. Monocotyledones. B. Dicotyledones.

Ray was the first botanist who recognised the importance of the one or two seed-leaves of the embryo, and initiated the division of the Flowering-plants into Monocotyledons and Dicotyledons.

System of LINNÆUS (1733).

In his well known artificial system Linnæus divided the Vegetable Kingdom into twenty-four classes, based upon the number, relative position and union of the stamens with regard to each other, and also to the gynœceum.

Class I. MONANDRIA. Flowers with 1 stamen. „ II. DIANDRIA. „ „ 2 stamens. „ III. TRIANDRIA. „ „ 3 „ „ IV. TETRANDRIA. „ „ 4 „ „ V. PENTANDRIA. „ „ 5 „ „ VI. HEXANDRIA. „ „ 6 „ „ VII. HEPTANDRIA. „ „ 7 „ „ VIII. OCTANDRIA. „ „ 8 „ „ IX. ENNEANDRIA. „ „ 9 „ „ X. DECANDRIA. „ „ 10 „ „ XI. DODECANDRIA. „ „ 11 to 19 stamens. „ XII. ICOSANDRIA. „ „ 20 or more stamens inserted on the calyx. „ XIII. POLYANDRIA. „ „ 20 or more stamens inserted on the receptacle. „ XIV. DIDYNAMIA. Stamens didynamous. „ XV. TETRADYNAMIA. „ tetradynamous. „ XVI. MONADELPHIA. Filaments united into 1 bundle. „ XVII. DIADELPHIA. „ „ „ 2 bundles. „ XVIII. POLYADELPHIA. „ „ „ several bundles. „ XIX. SYNGENESIA. Anthers united together. „ XX. GYNANDRIA. Stamens and pistil united. „ XXI. MONŒCIA. Flowers diclinous, ♂ and ♀ on the same plant. „ XXII. DIŒCIA. „ „ ♂ and ♀ on different plants. „ XXIII. POLYGAMIA. ♂-, ♀-, and ☿-flowers on the same plant. „ XXIV. CRYPTOGAMIA. Flowerless plants (Ferns, Mosses, Algæ, Fungi).

These classes were further divided into orders, according to the number of styles, as Monogynia, flowers with 1 style; Digynia, with 2 styles, etc. Thus a Dock (Rumex), having 6 stamens and 3 styles, would be placed in Class VI., HEXANDRIA, and Order III., Trigynia.

Class XIV. was divided into two orders. Order I., Gymnospermia, with seeds apparently naked, comprising the Labiatæ; and Order II., Angiospermia, with the seeds enclosed in a capsule (Bartsia, Rhinanthus).

Class XV. was divided into two orders: Order I., Siliculosa, fruit a silicula (Capsella); and Order II., Siliquosa, fruit a siliqua (Brassica).

Class XIX. was divided into Order I., Æqualis, all the flowers perfect (Sonchus); Order II., Superflua, flowers in the centre perfect, those at the circumference with pistils only (seemingly superfluous), e.g. Aster; Order III., Frustranea, flowers in the centre perfect, those at the circumference neuter, e.g. Centaurea.

“Fragments” of a natural system have also come down to us from Linnæus, who himself always recognised the imperfection of his artificial system.

System of ANTOINE LAURENT DE JUSSIEU (1789).

Class =Acotyledones.= Plants without cotyledons: Fungi, Ferns, Mosses, Algæ, Naiades I.

=Monoctyledones.= Plants with one cotyledon:-- 1. Stamens hypogynous II. 2. „ perigynous III. 3. „ epigynous IV.

=Dicotyledones.= Plants with two cotyledons:--

{ Stamens epigynous V. 1. APETALÆ { „ perigynous VI. { „ hypogynous VII.

{ Corolla hypogynous VIII. 2. MONOPETALAE { „ perigynous IX. { „ epigynous, {anthers connate X. { „ free XI.

{ Stamens epigynous XII. 3. POLYPETALÆ { „ hypogynous XIII. { „ perigynous XIV.

4. DICLINES IRREGULARES, male and female flowers on different plants, corolla generally absent.

System of A. P. DE CANDOLLE (1819).

I. =Vasculares.= Plants with vascular bundles. 1. EXOGENÆ. Vascular bundles arranged in a ring. A. Diplochlamydeæ. Calyx and corolla present. a. Thalamifloræ. Corolla polypetalous and hypogynous. b. Calycifloræ. Corolla perigynous or epigynous; stamens inserted on the calyx. c. Corollifloræ. Corolla gamopetalous; stamens inserted on the corolla. B. Monochlamydeæ. Perianth simple. 2. ENDOGENÆ. Vascular bundles scattered, the youngest in the centre. A. Phanerogamæ. Flowers present. B. Cryptogamæ. Flowers absent. II. =Cellulares.= Vascular bundles absent. 1. FOLIACEÆ. Leaves present. 2. APHYLLÆ. Leafless.

ROBERT BROWN published in 1827 his discovery of the gymnospermy of the ovules of the Coniferæ and Cycadeæ, and showed that the Gymnosperms, which had previously been classed with the Dicotyledons, must be regarded as an independent group.

System of STEPHEN ENDLICHER (1836–40).

I. =Thallophyta.= No differentiation into stem and root. 1. PROTOPHYTA. Class I., Algæ; Class II., Lichenes. 2. HYSTEROPHYTA. Class III., Fungi. II. =Cormophyta.= Differentiated into stem and root. 1. ACROBRYA. Stem growing at the point. Anophyta (Hepaticæ, Musci). Protophyta (Filices, etc.). Hysterophyta (Balanophoreæ, etc.). 2. AMPHIBRYA. Stem growing at the circumference (Monocotyledons). 3. ACRAMPHIBRYA. Stem growing both at the point and circumference. Gymnosperma (Coniferae). Apetala. Perianth single or absent. Gamopetala. Petals gamopetalous. Dialypetala. Petals polypetalous.

System of A. BRONGNIART (1843).

I. =Cryptogamæ.= Plants without flowers. 1. AMPHIGENÆ. Not differentiated into stem or leaf (Algæ, Fungi, Lichenes). 2. ACROGENÆ. Plants with stem and leaf (Muscineæ, Filicinæ). II. =Phanerogamæ.= Plants with flowers. 3. MONOCOTYLEDONES. a. Albuminosæ. Seeds with endosperm. b. Exalbuminosæ. Seeds without endosperm. 4. DICOTYLEDONES. a. Angiosepermæ. α. Gamopetalæ. β. Dialypetalæ. b. Gymnospermæ.

System of JOHN LINDLEY (Vegetable Kingdom, 1845).

Asexual, or Flowerless Plants.

Stem and leaves undistinguishable I. =Thallogens.= Stem and leaves distinguishable II. =Acrogens.=

Sexual, or Flowering Plants.

Fructification springing from a thallus III. =Rhizogens.= Fructification springing from a stem. Wood of stem youngest in the centre; cotyledon single. Leaves parallel-veined, permanent; wood of stem always confused IV. =Endogens.=

Leaves net-veined, deciduous; wood of the stem, when perennial, arranged in a circle with a central pith V. =Dictyogens.=

Wood of stem youngest at the circumference, always concentric; cotyledons, 2 or more. Seeds quite naked VI. =Gymnogens.= Seeds inclosed in seed-vessels VII. =Exogens.=

System of ALEXANDER BRAUN (1864).

I. =Bryophyta.= 1. THALLODEA (Algæ, Fungi, Lichenes). 2. THALLOPHYLLODEA (Charas, Mosses). II. =Cormophyta.= 1. PHYLLOPTERIDES (Ferns, Equisetums). 2. MASCHALOPTERIDES (Lycopods). 3. HYDROPTERIDES (Water-ferns). III. =Anthophyta.= GYMNOSPERMÆ. 1. Frondosæ (Cycadeæ). 2. Acerosæ (Coniferæ). ANGIOSPERMÆ. 1. Monocotyledones. 2. Dicotyledones. Apetalæ. Sympetalæ. Eleutheropetalæ.

W. HOFMEISTER published from 1849 to 1851 his researches upon the embryology of the Phanerogams, and upon the embryology and life-history of the Vascular Cryptogams, and established the phylogenetic connection existing between the Mosses, Vascular Cryptogams and Phanerogams.

System of HOOKER and BENTHAM (Genera plantarum, 1862–1883).

Dicotyledones.

I. Polypetalæ.

Series I. =Thalamifloræ.= Calyx most often free from the ovary. Petals uniseriate or often 2–∞-seriate. Stamens ∞ or definite, inserted on the receptacle, often small, or raised, or stipitate. Ovary most frequently free.

Cohort I. RANALES. Stamens ∞, or if definite the perianth is 3–∞-seriate. Carpels apocarpous, or immersed in the receptacle. Endosperm usually abundant, fleshy.

Order 1. Ranunculaceæ. „ 2. Dilleniaceæ. „ 3. Calycanthaceæ. „ 4. Magnoliaceæ. „ 5. Anonaceæ. „ 6. Menispermaceæ. „ 7. Berberideæ. „ 8. Nymphæaceæ.

Cohort II. PARIETALES. Stamens ∞ or definite. Ovary unilocular, or divided into loculi by spurious dissepiments, with parietal placentation. Endosperm absent or fleshy.

Order 9. Sarraceniaceæ. „ 10. Papaveraceæ. „ 11. Cruciferæ. „ 12. Capparideæ. „ 13. Resedaceæ. „ 14. Cistineæ. „ 15. Violarieæ. „ 16. Canellaceæ. „ 17. Bixineæ.

Cohort III. POLYGALINÆ. Stamens definite. Ovary usually perfectly or imperfectly bilocular. Micropyle often superior. Fruit very often compressed laterally. Endosperm very often abundant and fleshy.

Order 18. Pittosporeæ. „ 19. Tremandreæ. „ 20. Polygaleæ. „ 20_a._ Vochysiaceæ.

Cohort IV. CARYOPHYLLINEÆ. Stamens definite, or rarely ∞. Ovary unilocular, or imperfectly septate. Placenta central, more rarely parietal. Micropyle inferior. Embryo curved, rarely straight. Endosperm farinaceous.

Order 21. Frankeniaceæ. „ 22. Caryophylleæ. „ 23. Portulaceæ. „ 24. Tamariscineæ.

Cohort V. GUTTIFERALES. Sepals inbricate. Stamens usually ∞. Ovary septate, placentæ on the inner angles of the loculi. Endosperm absent or fleshy.

Order 25. Elatineæ. „ 26. Hypericineæ. „ 27. Guttiferæ. „ 28. Ternstrœmiaceæ. „ 29. Dipterocarpeæ. „ 30. Chlænaceæ.

Cohort VI. MALVALES. Sepals valvate. Stamens usually ∞ or monadelphous. Ovary septate, placentæ on the inner angles of the loculi. Endosperm absent or fleshy.

Order 31. Malvaceæ. „ 32. Sterculiaceae. „ 33. Tiliaceæ.

Series II. =Discifloræ.= Calyx usually free from the ovary. Petals uniseriate. Stamens usually definite, inserted within, or upon, or around the receptacle, which is more often expanded as a disc. Ovary usually free, or embedded in the disc.

Cohort VII. GERANIALES. Disc usually as a ring between the stamens, or adnate to the staminal tube, or reduced to glands alternating with the petals, more rarely absent. Gynœceum entire, or more often lobed, or sub-apocarpous. Ovules most often 1–2 in each loculus, pendulous, raphe ventral. Leaves various.

Order 34. Lineæ. „ 35. Humiriaceæ. „ 36. Malpighiaceæ. „ 37. Zygophylleæ. „ 38. Geraniaceæ. „ 39. Rutaceæ. „ 40. Simarubeæ. „ 41. Ochnaceæ. „ 42. Burseraceæ. „ 43. Meliaceæ. „ 44. Chailletiaceæ.

Cohort VIII. OLACALES. Disc cupular or annular, free, or bearing the stamens and petals on its edge. Gynœceum entire. Ovules 1–3 in the unilocular ovaries, or 1–2 in each loculus, pendulous, raphe dorsal. Leaves simple.

Order 45. Olacineæ. „ 46. Ilicineæ.

Cohort IX. CELASTRALES. Disc tumid, adnate to the calyx, or covering its base. Stamens inserted round the disc or affixed to its margin. Gynœceum usually entire. Ovules most often two in each loculus, erect, raphe ventral. Leaves simple, or rarely compound.

Order 47. Celastrineæ. „ 48. Stackhousieæ. „ 49. Rhamneæ. „ 50. Ampelideæ.

Cohort X. SAPINDALES. Disc various. Stamens variously inserted on the disc. Gynœceum entire, or more often lobed, or sub-apocarpous. Ovules more often 1–2 in each loculus, ascending with ventral raphe, or reversed, or solitary and pendulous from an ascending funicle, or rarely ∞ horizontal. Leaves pinnate, or more rarely simple or digitate.

Order 51. Sapindaceæ. „ 52. Sabiaceæ. „ 53. Anacardiaceæ.

Anomalous orders, or rather genera,--

Order 54. Coriarieæ. „ 55. Moringeæ.

Series III. =Calycifloræ.= Calyx-tube usually surrounding the ovary, or adnate to it. Petals uniseriate, inserted on the calyx-tube. Stamens ∞ or definite, inserted on the calyx-tube, or most often on the disc lining the calyx-tube. Ovary often enclosed by the calyx-tube, or inferior.

Cohort XI. ROSALES. Carpels solitary, or free, or united at the base, more rarely at the apex; styles distinct, or very rarely united into a column, and easily separated.

Order 56. Connaraceæ. „ 57. Leguminosæ. „ 58. Rosaceæ. „ 59. Saxifrageæ. „ 60. Crassulaceæ. „ 61. Droseraceæ. „ 62. Hamamelideæ. „ 63. Bruniaceæ. „ 64. Halorageæ.

Cohort XII. MYRTALES. Ovary syncarpous, inferior, or enclosed in the calyx-tube, usually divided into loculi; style undivided. Ovules 2–∞ in the loculi.

Order 65. Rhizophoreæ. „ 66. Combretaceæ. „ 67. Myrtaceæ. „ 68. Melastomaceæ. „ 69. Lythrarieæ. „ 70. Onagrarieæ.

Cohort XIII. PASSIFLORALES. Ovary syncarpous, inferior or superior, enclosed in the calyx-tube or exserted, unilocular with parietal placentation, or divided into loculi; styles distinct, one style divided, or undivided.

Order 71. Samydaceæ. „ 72. Loaseæ. „ 73. Turneraceæ. „ 74. Passifloreæ. „ 75. Cucurbitaceæ. „ 76. Begoniaceæ. „ 77. Datisceæ.

Cohort XIV. FICOIDALES. Ovary syncarpous, inferior or superior, divided into loculi with sub-basilar placentæ, or more rarely unilocular with parietal placentæ. Styles distinct, or divided at the apex. Embryo curved or excentric.

Order 78. Cacteæ. „ 79. Ficoideæ.

Cohort XV. UMBRELLALES. Ovary syncarpous, inferior, crowned by the disc, divided into loculi, or unicarpellate. Styles distinct or divided at the apex. Ovules solitary and pendulous in the loculi.

Order 80. Umbelliferæ. „ 81. Araliaceæ. „ 82. Cornaceæ.

II. GAMOPETALÆ.

Series I. =Inferæ.= Ovary inferior. Stamens equal to the lobes of the corolla, rarely fewer.

Cohort I. RUBIALES. Stamens adnate to the corolla. Ovary 2–∞-locular, loculi 1–∞-ovuled.

Order 83. Caprifoliaceæ. „ 84. Rubiaceæ.

Cohort II. ASTERALES. Stamens adnate to the corolla. Ovary formed of 2 carpels, unilocular and 1-ovuled.

Order 85. Valerianeæ. „ 86. Dipsaceæ. „ 87. Calycereæ. „ 88. Compositæ.

Cohort III. CAMPANALES. Stamens generally free from the corolla. Ovary 2–6-locular, loculi most often ∞-ovuled.

Order 89. Stylidieæ. „ 90. Goodenovieæ. „ 91. Campanulaceæ.

Series II. =Heteromeræ.= Ovary most often superior. Stamens free from the corolla, opposite to, or double the lobes of the corolla, or ∞, or if epipetalous, equal and alternating with them. Carpels more than 2.

Cohort IV. ERICALES. Stamens double the lobes of the corolla, or alternating with them. Ovary 2–∞-locular. Seeds small, frequently minute.

Order 92. Vacciniaceæ. „ 93. Ericaceæ. „ 94. Monotropeæ. „ 95. Epacrideæ. „ 96. Diapensiaceæ. „ 97. Lennoaceæ.

Cohort V. PRIMULALES. Stamens equal to and opposite the lobes of the corolla. Ovary unilocular, with a free central placenta, 1–∞ ovules.

Order 98. Plumbagineæ „ 99. Primulaceæ. „ 100. Myrsineæ.

Cohort VI. EBENALES. Stamens equal to and opposite the lobes of the corolla, or double, or ∞. Ovary 2–∞-locular. Seeds few and large. Trees or shrubs.

Order 101. Sapotaceæ. „ 102. Ebenaceæ. „ 103. Styraceæ.

Series III. =Bicarpellatæ.= Ovary most often superior. Stamens equal, or fewer than the lobes of the corolla, and alternating with them. Carpels 2, rarely 1 or 3.

Cohort VII. GENTIANALES. Corolla regular. Stamens equal to the lobes of the corolla, or if fewer, usually alternating with the carpels. Leaves generally opposite.

Order 104. Oleaceæ. „ 105. Salvadoraceæ. „ 106. Apocynaceæ. „ 107. Asclepiadeæ. „ 108. Loganiaceæ. „ 109. Gentianeæ.

Cohort VIII. POLEMONIALES. Corolla regular. Stamens equal to the lobes of the corolla. Leaves generally alternate.

Order 110. Polemoniaceæ. „ 111. Hydrophyllaceæ. „ 112. Boragineæ. „ 113. Convolvulaceæ. „ 114. Solanaceæ.

Cohort IX. PERSONALES. Corolla most often irregular or oblique. Posterior stamen less than the others, more often reduced to a staminode, or altogether absent. Ovary ∞-ovuled, or 2-ovuled.

Order 115. Scrophularineæ. „ 116. Orobanchaceæ. „ 117. Lentibularieæ. „ 118. Columelliaceæ. „ 119. Gesneraceæ. „ 120. Bignoniaceæ. „ 121. Pedalineæ. „ 122. Acanthaceæ.

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