Flowers : their origin, shapes, perfumes, and colours

Front matter

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Chapter I

THE OLD AND THE NEW PHILOSOPHY OF FLOWERS, PAGE Old notions as to use of flowers — Religion and science — ~

The higher ground occupied by modern botany — Extinct types of vegetation —- Erroneous ideas as to origin of “thorns,” “thistles,” &c. — Fallacy of the theory that flowers were created specially to delight mankind — Appearance of flowers before man — Richness of the Miocene flora — The evolution theory — Unity of creation — Distribution of flowers where man cannot see them — Flower-clad and flowerless islands — Flowers and their poetical associations — Poisonous plants — Reason why flowers exist — Cross-fertilization and the means taken by plants to effect it — Shapes and colours of flowers — Inconspicuous flowers usually crossed by the wind — Entomophilous and anemophilous flowers — Development of senses of sight and smell in insects — Pollen of wind-crossed and insect-crossed flowers different — Night-flowering plants and their colours — Relations between certain flowers and certain insects — Influence of atmosphere in manufacturing towns on flowers and insects — Antiquity of butterflies and moths SR ee coe ar Tey I

Chapter II. The Geological Antiquity Of Flowers And Insects

Imperfection of the geological record as regards plants — Conditions on which the fossilization of plants depends — Estuarine and lacustrine strata and their contents — The floral records of the rocks — Geological

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PAGE succession of vegetable types — Botanical embryology and teratology — Ages of ferns, conifers, and true-seeding plants — Proportion of these groups in different geological formations — Flower-visiting insects, their geological order of appearance — Late introduction of true. flowers and flower.visiting insects — Geological antiquity of certain orders of insects — Formations in which their remains have been found — Supposed fossil butterfly in Oolitic strata — Tertiary butterflies — Generalized character of primeval insects — Liassic insects — Purbeck ditto — Insects in Stonefield slates — Tertiary insects — Abundance of fossil insects in Miocene beds of GEningen — Professor Heer on ditto — Percentage of orders of ditto— Abundance of flower-haunting insects — Fossil insects in American Tertiary deposits — Geographical distribution of insects since Miocene epoch — First appearance of flowers — Wind-fertilized flowers preceded insect-fertilized — Cretaceous floras of Old and New Worlds — Order of appearance of various types of flowers, as polypetalous and gamopetalous — Eocene flora of Hampshire — First appearance of composite flowers — An American flora in Europe — Influence of glacial period on distribution of floras — Correlation of appearance in time between certain orders of insects and flowers ++ «+ «+ «+ 22

Chapter III. The Geographical Distribution Of Flowers

Conditions affecting distribution of flowers — Agencies of distribution — Adaptability of floras to climates, &c. — Centres of creation — Various kinds of floras, as “ Arctic,” tropical,” &c.— Maritime plants and their distribution — Plants and certain soils — Zones of vegetation, lateral and vertical — Difference in character of floras of same latitude — Reason for plants not growing in England not because of absence of suitable conditions — Floral outliers — Conspicuous and zuconspicuous floras — Reasons for their distri-

CONTENTS. iX

PAGE bution — Geological and biological causes affecting plant distribution — Extensive distribution of lowly organized plants — Ditto of grasses and conifers — Limited distribution of Cycadacee, Sequoias, Banksias, &c.— Geological antiquity of these groups — Influence of Glacial period in breaking up ancient floras — Difference in time of flowering of same plants according to climate, &c.— Changes in fauna of a country affect plants— The Yucca and its insects — Distribution of plants by animal agency — Arborescent Composit@a ~ Wallace on fragmentary character of islandic floras — The Pringlea and its surroundings — Floras of Sandwich Islands, Tahiti, Juan Fernandez, Galapagos Islands, Kerguelen’s Land, &c.— Birds and flowers — Composite flowers — Arctic and Alpine flowers and

insects —Character of Arctic floras Pi erstue re epahemar 53

CHAPTER IV. GEOGRAPHICAL DISTRIBUTION OF FLOWERS—continued

Dr. Croll on changes of terrestrial climate during the geological epochs — “ Eocene” and “ Glacial” epochs — Abundant traces of glacial action at equator and in southern hemisphere — Influence of glacial climates on migration of Arctic and Antarctic plants — Anomalous distribution of ditto thus explained — European plants in Africa and Java— Distribution of the Proteacee — Arctic flora of Great Britain, its origin— Ditto of the Alps and Pyrenees — Results of shallow and deep water between islands and continents — Flora of the Malayan Archipelago — Ditto of West Indian Islands — Ditto of Galapagos Islands — Ditto of Madagascar — Ditto of Mauritius — Geological history of the Desert of Sahara — Sclater and Wallace on the six great natural history provinces of the world — Flora of the Cape of Good Hope — Ditto of the Amazons and its tributaries — Ditto of Australia — Antiquity of the North American flora — Geological changes as affecting plant distribution -- -- . 73

Chapter V. The Structure Of Flowering Plants

The life of a plant — Vegetation and reproduction —

Variety of organs in plants — Goethe and Wolff’s theory as to simplicity of a plant’s structure — Stem and bark — Leaf-buds and flower-buds — How the latter may be transformed from former — Results of excess and deficiency of plant nutrition — Leaf-buds of various plants — Origin of reproductive organs — Transformation or “monstrous” condition of ditto — Stomata of leaves — Functions of leaves — Spiral arrangement of ditto on stalks — Reason for this — Reason for various sizes and shapes of leaves — Influence of sunlight on leaves— Phyllotaxy, or order of leaf-succession — Results of suppression of internodes — Difference of shapes in leaves of same plant, as bramble — Simplicity of ancient types of flowers — Scarlet bracts in Poznsettta — How they do duty for petals — Polypetalous and gamopetalous flowers — Spores and pollen-grains — Radicle leaves — Difference in shapes of leaves of aquatic plants — “ Carnivorous” plants, how they originated — Modifications of leaves — Underground stems oe oe ee anit oe o- oe oe

CHAPTER VIL

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RELATIONS BETWEEN FLOWERS AND THEIR PHYSICAL

SURROUNDINGS.

Origin of orders, genera, species, and varieties of plants

— Time occupied in developing them — Difficulty of arranging plants in a natural ascending series — Lowest orders of flowering plants and highest ditto of cryptogamous plants — Antiquity of certain orders of aquatic plants — Extensive geographical distribution of ditto

CONTENTS.

— The duckweeds, starworts, sea-wrack, pondweeds, millefoils, Ruppia, &c.— The Vallisneria and its distribution — Singular structure of flowers of ditto — Mare’s tails, hornworts, &c.— Inconspicuous: flowers — Relation between latter and attractive flowers — Geranium sylvaticum and G. pusillum — Geological antiquity of certain parasitic fungi — Origin of parasitic flowering plants — The dodder, broom-rape, toothwort, &c.— The mistletoe and its relations — Monstrosities and parasitism — Frequency of both habits in Scrophulariacee — Epiphytal. orchids — Battle of life in tropical forests — Utility of epiphytal habits to orchids — Fossil orchids — Origin of orchids — Primeval floras — Arboreal floras—Soda-loving plants— Heat- and cold-loving plants — Carnivorous ditto

Chapter VII. Relations Between Flowers And The Wind

Researches of modern botanists — Co-ordination between / insects and flowers — Ditto between flowers and the wind — Necessity for cross-fertilization in all anemophilous flowers —A battle for life in a green lane — Nature forbids the banns of intermarriage — Flowers and crossing — Structures of wind-fertilized or anemophilous flowers — Shapes of their pollen-grains — Abundant production of ditto — Cause of “ hay-fever ” — Peculiarity of stamens of grasses — Catkins, structure of — Reason why flowers of catkin-bearing flowers appear before the leaves — Proterogynous flowers — Plumose structure of pistils of wind-fertilized flowers — Flowers of pines, nettles, pellitory, hop, oak, &c. — Staminate and pistillate flowers — Flowers of the ash, dog’s mercury, maple, &c. Sorin Ves

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Chapter VIII. The Colours Of Flowers

\ PAGE Poetical associations of coloured flowers — Origin of colours in petals — Change of colour in autumnal leaves — Petals are degraded or modified leaves — The purple nettle, Coleus, Poinsettia, &c. — Structural origin of floral organs — Colours specially attract insects — Coloured sepals — Geological antiquity of certain orders of flowers — White or night-flowering plants — Flowers of lilies, tulips, hyacinths, squills, fritillary, &c. — Perianthed flowers — Flowers of iris, gladiolus, water plantain, flowering rush, arrow-head, frog-bit, &c. — Reason for night-opening flowers being white — Moths. and flowers — Flowers of narcissus, snowdrop, daffodils, jonquils, &c. — Perianthed flowers of orchids — Variety in shape and size of ditto — Flowers of Labiate — Absence. of corollas — Change of colour in calyx — Meadow rue, marsh marigold, larkspur, monkshood, columbine, anemones, &c. — Origin of veins in petals — Flowers of Ranunculus, poppy, Escholtzia, harebell, bilberry, fuchsia, Dzelytra, Corydalis, Tropeolum, Polygala, &c. — Flowers of Poznsettia, Bougainvillea, &c. — Ditto of Arum, Helichrysum, grass of parnassus, cyclamen, Dodecatheon, Myosotis, viper’s bugloss, comfrey, &c. — Variety of colours in same inflorescence — Change of colours in same flowers — Hzbiscus mutabilis, Gladiolus versicolor, Anagallis arvensis, Anemone patens, &c.— Distribution of colour on corolla — Varies with difference in shape of petals — Umbelliferous flowers — Sweet william — Relative duration of inflorescences of flowers — Tamarisk — Interdependence of insects and flowers we twee ee | ee ey ne er er

CONTENTS. Xiil

Chapter IX. The External Shapes Of Flowers

PAGE Adaptation of shapes of flowers to insect visitation—General and special adaptations necessitate different shapes — . Flowers of foxglove, wild rose, strawberry, &c. — Polypetalous flowers — Structure of flowers in Crucifere — Adaptation of ditto to insects — Relation between polypetalous and gamopetalous flowers — Flowers of carnation, convolvulus, snapdragon, sage, &c. — Modification of papilionaceous flowers — Relations between calyx and corolla — Structure of corolla of common pea — Structure of labiate flowers — Structure of orchids — Singular variety in shapes of flowers of Scrophulariacee — Symmetrical and bilateral types of flowers — Herbert Spencer on ditto — Special adaptations in shapes of flowers to certain insects — Instances of this in the orchid family — Darwin on ditto — Peculiarity of bee orchis — Parthenogenesis — Cletstogamic flowers — Tubed flowers and insects — Honeysuckles and hawk-moths — Madagascar orchids — Drooping flowers, as lily of the valley, snowdrop, harebell, &c. — Flowers of daffodil, Passzflora, &c. — Modifications in petals — Small flowers and their numbers — Grass pea and clovers — Intermediate flowers — Dipterous flies and pollen — Origin of staminate and pistillate flowers — Structure of clezstogamic flowers — Origin of ditto— Variety in shapes and sizes of ditto—- Utilitarian reason for ditto— Underground clezstogamic flowers — Floral vicariousness ++ 203

Chapter X. The Internal Shapes Of Flowers

Wonderful degree to which modification of floral organs is carried — Mostly directed to ensure crossing, or to prevent self-fertilization — The azthers and their filaments — Proterandrous and proterogynous flowers

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PAGE — Reasons for ditto — Flowers of pinks, geraniums, willow-herbs, mallows, campanulas, gentians, &c. — Flowers of figwort, birthwort, &c. — Prepotency of foreign pollen over a flower’s own pollen — Dimorphism in flowers, as in common primrose — Ditto in cowslip, auriculas, water violet, bog-bean, &c. — Trimorphism, as in flowers of purple loosestrife— Darwin on ditto — Comparison between pollen-grains of wind- and insect-fertilized flowers — Reason for irritability of stamens of berberry, &c. — Pollinia of orchids — Pollen of Azalea, Rhododendron, &c. — Aborted stamens — Arrangement of stamens in flowers — Utility of hairs in flowers — Floral pollen-brushes — Structure of hairs in birthwort and cuckoo - pint — Floral enigmas and charades oe. ee | a ee) Ge ne Be SS be ke)

Chapter XI. The Perfumes Of Flowers

Delightful associations of floral perfumes — Divisibility of matter emitting perfumes — A “language of smell” — Dr. Piesse and chorded perfumes — Imitation of floral perfumes by modern chemists —Hydro-carbon compounds, their instability — Influence of light and heat in changing them — Perfume of Magnolia tripetala — Perfumes of rosaceous flowers — Coumarin — Perfume of jonquil and narcissus — Disagreeable odours of flowers — Ditto of Raffesza, Iris, goosefoot, &c.— Character of flowers of Stapelias — Perfumes of lime-flowers — Perfumes most abundant in white flowers — Reasons for ditto — Intensity of perfumes — Cactus grandiflora — Perfume of nectar or floral honey — Origin of nectaries or honey-glands—Honey-glands elsewhere than in corollas— Mr. Belt on ditto — Position of nectaries.in flowers— Relation of ditto to various insects — Structural changes in flowers ++ 254

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Chapter XII. Social Flowers

PAGE Inflorescence of small flowers — Arrangement of ditto so as to produce most effect — Grouping of flowers on stems — Flowers of field madder, centaury, cinchona, elder, guelder-rose, &c. — Barren flowers of guelder-rose, corn-cockle, hydrangea, &c. — Reason for ditto — Difference in size and shape of flowers in umbels — Flowers of wild carrot, angelica, chervil, &c.— Relation between small flowers and small insects — Proterandrous character of many umbelliferous flowers.— Flowers of Heracleum, knapweed, A strantia, &c. — Division of floral labour — This principle carried out most in Composzte — Structure of ox-eye daisy —A daisy a colony of florets or small flowers — Outer florets or petals barren — “ Early closing ” flowers — Reasons for such a habit — “ Monstrosities ” of daisy — Uses of petals to composite flowers — Why these flowers change when cultivated — Flowers of groundsel, Helichrysum, Guaphalium, chicory, nipplewort, &c.— Modifications of composite flowers -- ++ 268

Chapter XIII. Birds And Flowers

British flowers more directly related to insects than birds — Birds cross flowers in America, Africa, Asia, and Australia — Sun-birds, humming birds, brush-tongued parakeets, and honey -eaters — Relations between brush-tongued parakeets and Australian flora— The sun-birds and the “ bush” flora— Mr. Belt on fertilization of Marcgravia by humming birds— Shapes of certain tropical flowers related to crossing by birds ~ Honey-eaters and Metrosideros — Humming birds and flowers of Lrythrina — Various flowers habitually

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PAGE crossed by humming birds — S¢redztza and sun-birds — New Zealand birds and flowers — Birds and fruit — Colours of fruit intended to attract attention of birds — Birds distribute seeds — Reasons for fleshy pericarps in fruits — Coloured seeds and their distribution — Birds can partake of poisonous berries — General relations between birds and fruits ++ ++ ++ «+ «2 «+ «+ 292