Letter XLVIII
HISTORY OF ENTOMOLOGY.
After the very general idea that I have attempted to embody for you of the System of Insects; of the groups in which nature has arranged them, and their mutual relations; it will not be out of place, if I next state to you what has been effected by Entomologists towards reducing them to order: or, in other words, if I give you some account of the various Methods and Systems[1316], beginning with the earliest, that have appeared and had their day, which will include a history of the progress of our science from its commencement to its present era.
In writing the history of any science, two modes present themselves. We may either give a chronological review of all the circumstances and publications connected with it; or content ourselves with a rapid survey, dwelling only on the principal epochs, and those lights of the science who by their immortal labours gave birth to them. The latter is that on every account best suited to our present purpose, which I shall therefore here adopt.
There seem to me to be seven principal epochs into which the History of Entomology may be divided: viz. 1. The Era of the Ancients. 2. The Era of the revival of the science after the darkness of the middle ages. 3. The Era of Swammerdam and Ray, or of the Metamorphotic System. 4. The Era of Linné, or of the Alary System. 5. The Era of Fabricius, or of the Maxillary System. 6. The Era of Latreille, or of the Eclectic System. And 7. The Era of MacLeay, or of the Quinary System. All of these appear to form important points, or resting-places, in the progress of the science towards its acme; and of each of these I shall now proceed to give you a brief account.
1. The Era of the Ancients. To ascertain what attention was paid to insects in the earliest ages, we must have recourse to the most ancient of records, the Old Testament. In this sacred volume we are informed that after the Creation GOD brought the creatures to Adam that he might name them[1317]. Now the first man, in his unimpaired state of corporeal, mental, and spiritual soundness, under the divine guidance, doubtless imposed upon them names significant of their qualities or structure; which according to Plato was a work above human wisdom, and on account of which the ancient Hebrews deduced that Adam was a philosopher of the highest endowments[1318]. Whether on this great and interesting occasion he gave names to individual species, or only to natural groups, does not clearly appear. But probably as they were created, so were they brought before him "According to their kinds[1319]."
Subsequently Moses will be thought to have possessed no ordinary knowledge of insects, if we suppose, as the ingenious remarks of Professor Lichtenstein[1320] render probable, that he distinguishes as clean insects the Fabrician genera Gryllus, Locusta, Truxalis, and Acheta, which a person unobservant of these animals would have confounded together. This discrimination presupposes this knowledge of their general characters, not only in the Jewish lawgiver, but also in the people themselves to whom the precept was addressed, to whom it would otherwise have been de ignotis.
Allusion is made in Holy Writ to insects of almost every one of the modern Orders[1321]. They are represented as employed divinitùs sometimes to annoy the enemies of the Israelites, and at others to punish that people themselves when they apostatized from their God. The prophets frequently introduce them as symbols of enemies that lay waste or oppress the church: as the fly of the Ethiopians or Egyptians; the bee of the Assyrians; and the locust of the followers of Mahomet and other similar destroyers[1322]. That Solomon, amongst other objects to the investigation of which his divinely inspired wisdom directed him, did not deem insects, those "Little things upon the earth[1323]," unworthy of his attention, we know from Scripture[1324]; but as his physical writings are lost, we are ignorant whether he treated of their natural arrangement, their economy and history, or of the instruction they afford analogically considered. Where he has referred to them incidentally, it is generally with this latter view.
If we turn from the word and people of GOD to the Lovers of Wisdom (as they modestly styled themselves) of the heathen world, and their writings; we shall discern amongst them a great light shining, the beams of which illuminate even our own times. In the illustrious Stagyrite we recognize--"The father of philosophy, at least of our philosophy, who, rising superior to the darkness in which he lived, darted his penetrating glance through all nature, and established principles which a long course of ages of inquiry have but confirmed. With Aristotle begins the real History of science: and how much soever he may have erred upon particular points, the greatness of his conceptions and the justness of his ideas, on the whole entitle him to our high veneration. His labours in the investigation of the Animal Kingdom have laid the foundation of the knowledge we now possess[1325]." This language of the lamented and learned President of the Linnean Society is particularly applicable to what this great and original genius has effected in Entomology. We have seen upon a former occasion[1326], that Linné himself had not those precise ideas of the limits of the Class Insecta, which Aristotle so many centuries before him had adopted. In stating the obligations of Entomology to this true sçavant, I shall begin by laying before you a tabular view of what may be called his system, as far as I have been able to collect it from his works, especially his History of Animals.
{ Coleoptera[1327]. { Pedetica = Orthoptera saltatoria { Latr.[1328] { Astomata = Hemiptera Latr.[1329] { Psychæ = Lepidoptera[1330]. { { Pterota vel { { majora = Neuroptera { Ptilota[1331] { Tetraptera { L. _Orthoptera { { { cursoria_ Latr.[1332]? { { { Opisthocentra = { { { Hymenoptera[1333]. { { { { { Diptera[1334] { minora = Musca, { { { Tipula, &c. Insecta { { { Emprosthocentra = { { { Culex, { { { Stomoxys, { { { Tabanus, &c. { { { Pterota simul { Myrmex = Formica L. { et Aptera[1335] { Pygolampis = Lampyris L. { { Aptera[1336].
It may be further stated, that Aristotle perceived also the distinction between the Mandibulata and Haustellata of modern authors: for he observes, that some insects having teeth are omnivorous; while others, that have only a tongue, are supported by liquid food[1337]. He appears to have regarded the Hymenoptera, or some of them, as forming a third subclass; since he clearly alludes to them, when he says that many have teeth, not for feeding, but to help them in fulfilling their instincts[1338].
From the above statement it will appear that this great philosopher had no contemptible notion,--though he has only distinguished three of them as larger groups by appropriate names,--of the majority of the Orders of Insects at present admitted. His Coleoptera, Psychæ, and Diptera are evidently such. His idea of Hemiptera seems taken solely from the Cicada or Tettix: but the manner in which he expresses himself concerning it, as having no mouth, but furnished instead with a linguiform organ resembling the proboscis of Diptera[1339], proves that he regarded it as the type of a distinct group. Since he considers the saltatorious Orthoptera as forming such a group, it is probable that he included the cursorious ones with the Neuroptera in his majora section of Tetraptera; and the resemblance of many of the Mantidæ to the Neuroptera is so great, that this mistake would not be wonderful. His division of the Diptera is quite artificial.
How far Aristotle's ideas with regard to genera and species attained to any degree of precision, is not easily ascertained: in other respects his knowledge of insects was more evident. As to their anatomy, he observes that their body is usually divided into three primary segments,--head, trunk, and abdomen; that they have an intestinal canal,--in some straight and simple, in others contorted,--extending from the mouth to the anus; that the Orthoptera have a ventricle or gizzard[1340]. He had noticed the drums of Cicada, and that the males only are vocal. Other instances of the accurate observation of this great man might be adduced, but enough has been said to justify the above encomiums. His principal error was that of equivocal generation.
Little is known with regard to the progress of other Greek Naturalists in entomological science. It appears probable, from an epithet by which Hesiod distinguishes the spider--air-flying[1341], that the fact of these insects traversing the air was at that time no secret. Apollodorus, as we learn from Pliny[1342], was the first monographer of insects, since he wrote a treatise upon scorpions, and described nine species. But like many other Zoologists, by mistaking analogy for affinity, he has included a winged insect, probably a Panorpa, amongst his scorpions. From the time of Aristotle, however, to Pliny, no writer is recorded, with the exception of those before alluded to[1343], that appears to have attended much to insects. They are indeed incidentally noticed by Theophrastus, Dioscorides, Virgil, Ovid, &c., but without any material addition to the stock of entomological knowledge bequeathed to us by the Stagyrite. Even Pliny's vast compendium, as it professed to be, of the natural history of the globe, was in many respects little more than a compilation from that great philosopher. Still, however, though he does not appear to have paid much practical attention to insects,--which indeed, considering the extent of his views, was scarcely to be expected,--yet as a guide to the then state of entomological knowledge, and as an advocate for the study, which in the exordium of his eleventh book he has so eloquently and with so much animation defended from the misrepresentations of ignorance, Pliny has conferred a lasting obligation on the science. The last zoological writer of note was Ælian, who amongst other animals often mentions insects. He has, however, few original observations. One was, that scorpions are viviparous[1344]. From him we learn incidentally that artificial flies were sometimes used by Grecian anglers[1345].
2. The Era of the Revival of the Science. From the time of Pliny and Ælian 1400 years rolled away, in which scarcely any thing was done or attempted for Entomology or Natural History in general. During that long night the glimmer of only one faint luminary appeared to make a short and feeble twilight. In the middle of the thirteenth century Albertus Magnus (so called from his family name of Groot, and justly, if incredible labour could entitle a man to the appellation), devoted one out of twenty-one folio volumes to Natural History. In this work he professes not so much to give his own opinions, as those of the Peripatetic philosophers[1346]. He occasionally, however, relates the result of observations made by himself, which prove him to have been no inattentive student of nature. He mentions a voyage that he made for the purpose of collecting marine animals, and that he found of them ten different tribes or genera, and several species of each. Amongst these he particularizes the Cephalopoda, the Crustacea, the testaceous Mollusca, and some of the Radiata and Acrita, &c.[1347] He gives a very correct account of the pitfalls of Myrmeleon. Insects he distinguishes, excluding the Crustacea, by the denomination of Anulosa (Annulosa), which he appears to employ as a known term[1348]. He also calls them worms, describing butterflies as flying worms, flies as fly-worms, spiders as spider-worms; and what is still more extraordinary, the toad and the frog, which he includes amongst his Anulosa, he calls quadruped-worms[1349]!! Though it may appear so absurd to speak of these animals as insects, yet he had perhaps a deeper and more philosophical reason for this than we may at first be disposed to give him credit for. This would be the case if he separated these from the other reptiles and placed them amongst insects on account of their metamorphoses, mistaking perhaps an analogical character for one of affinity[1350]. Some of the Annelida, as Filaria and Lumbricus[1351], he also regarded as insects. I cannot gather from his desultory pages that he had any notion of a systematical arrangement of his Anulosa.
After the taking of Constantinople by the Turks in the middle of the fifteenth century, the light of learning, kindled by those of its professors who escaped from that ruin, appeared again in the West. The Greek language then began to be studied universally; and in consequence of the coeval invention of the art of printing, various editions of the great works of the ancients were published: amongst the rest those of the fathers of Natural History. From the perusal of these, the love of the sciences of which they treated revived in the West, and the attention of scientific men began to direct itself to the consideration and study of the works of their CREATOR. In the latter part of that century, a work entitled the Book of Nature appeared in the German language, in which animals and plants were treated of and rudely figured; as they were likewise most miserably in Cuba's Ortus Sanitatis, published in 1485, in which insects and Crustacea were described under the three different denominations of Animals, Birds, and Fishes; so that but little profit was at first derived from the writings of Aristotle, Invertebrate animals not being then even honoured with
"A local habitation and a name."
This unpromising and apparently hopeless state of the science proved, however, the dawn of its present meridian brightness.
The first attempt at a separate and systematical arrangement of insects subsequent to the times of Aristotle, was made in the ponderous volumes of Ulysses Aldrovandus, who, disregarding the Stagyrite, arranged insects according to the medium they inhabit, as you will see in the subjoined table:
{Membranacea {Favifica. {Anelytra { {Non Favifica. {Alata {Elytrota. {Farinosa. { {Pedata { { {Aptera {Paucipeda. I {Terrestria { { {Multipeda. n { {Apoda s { e { {Pedata {Paucipeda. c { { {Multipeda t {Aquatica { a {Apoda
This artificial and meager system, which mixed insects with Annelida, was adopted by Charlton and other authors; and even in the eighteenth century had a patron of great eminence, who, endeavouring to improve upon it, has rendered it still more at variance with nature and Aristotle: I mean the celebrated Vallisnieri, to whom in other respects, though in this he fell behind his age, the science was under great obligations. He divides insects into, 1. Those that inhabit vegetable substances living or dead. 2. Those that inhabit any kind of fluid and in any state. 3. Those that inhabit any earthy or mineral substances, dead bones, or shells. And 4. Those that inhabit living animals[1352].
The work that is usually called Mouffet's Theatrum Insectorum was produced in the present era, and was the fruit of the successive labours of several men of talent. Dr. Edward Wotton and the celebrated Conrade Gesner laid the foundation; whose manuscripts falling into the hands of Dr. Thomas Penny,--an eminent physician and botanist of the Elizabethan age[1353], much devoted to the study of insect,--he upon this foundation meditated raising a superstructure which should include a complete history of these animals; and with this view he devoted the leisure hours of fifteen years of his life to the study of every book then extant that treated of the science either expressly or incidentally, and to the description and figuring of such insects as he could procure; but before he had reduced his materials to order, in 1589 he was snatched away by an untimely death. His unfinished manuscripts were purchased at a considerable price by Mouffet, a contemporary physician of singular learning[1354], who reduced them to order, improved the style, added new matter, and not less than 150 additional figures; and thus having prepared the work for the press, intended to dedicate it to queen Elizabeth[1355]. Fate, however, seemed still to frown upon the undertaking, for before he could commit his labours to the press he also died, and his book remained buried in dust and obscurity till it fell into the hands of Sir Theodore Mayerne, baron d'Aubone, one of the court physicians in the time of Charles I., who at length published it, prefixing a Dedication to Sir William Paddy, baronet, M.D., in 1634; and it was so well received that an English translation appeared twenty-four years afterwards. The work thus repeatedly rescued from destruction was indisputably the most complete entomological treatise that had then appeared. And though the arrangement (in which there is scarcely any attempt at system) is extremely defective, the figures very rude, often incorrect, and sometimes altogether false,--yet as an introduction to the study of insects its value at that day must have been very considerable; and as a copious storehouse of ancient entomological lore, it has not even at present lost its utility.
One of the most remarkable works of the era we are upon was published at Lignitz in the year 1603, by Caspar Schwenckfeeld, a physician of Hirschberg, under the title of Theriotrophium Silesiæ. This was probably the first attempt at a Fauna that ever was made. In it animals are divided into quadrupeds, reptiles, birds, fishes, and insects. The Crustacea, Mollusca, and Zoophytes, are included under fishes. He says of the Spongiæ that they are moved by animalcula which inhabit them[1356]. Did he borrow this observation from Aristotle, or was it made by himself[1357]? It is singular that Linné should never allude to this work. Goedart, who belongs also to this era, is stated to have spent forty years of his life in attending to the proceedings of insects[1358]. But after this long study, his principal use to the science was the improvement he effected in the drawing and engraving of them,--for his figures, though sometimes incorrect and sometimes fabulous, were far superior to those of his predecessors.
3. The Era of Swammerdam and Ray, or of the Metamorphotic System. The great men whose names are here united, as they were cotemporary, so they agreed in founding their respective systems of insects on the same basis. To the former, however, is due the merit of being the first who assumed the metamorphoses of these animals as the basis of a natural arrangement of them; upon which the latter, in conjunction with his lamented friend Willughby, erected that superstructure which opened the door for the present improved state of the science. Swammerdam's system may be thus expressed in modern language:
{Class i. Metamorphosis complete[1359] = Aptera L.[1360] { { ii. ------ semicomplete {Orthoptera, { { Hemiptera. { {Libellulina, { { Ephemerina[1361]. { Insects { { {Coleoptera, { { { Hymenoptera, part of { { incomplete { Neuroptera and { iii. -----{ { Diptera[1362]. { { { { obtected Lepidoptera[1363]. { { iv. ---- coarctate {Ichneumones { { minuti L.[1364] { {Muscidæ, &c[1365].
It was a great point gained in the science to introduce the consideration of the metamorphosis, and to employ it in the extrication of the natural system: for though when taken by itself it will, as in the table just given, lead to an artificial arrangement, it furnishes a very useful clue when the consideration of insects in their perfect state is added to it. The tables contained in the Prolegomena to Ray's Historia Insectorum divide insects into those which undergo no change of form, and those which change their form. The arrangement of the former Αμεταμορφωτα was made by Willughby, who subdivided them into Apoda and Pedata. As the only insects included in the former section were the grubs of Œstri, the remainder being Annelida, they need not be included in our table. I have endeavoured to compress these tables into as small a space as possible, by using the Linnean terms for metamorphosis, and reducing Ray's tribes of Orthoptera, Hemiptera, and Neuroptera to their modern denominations.
Ray details at considerable length the various tribes belonging to the four classes of metamorphosis established by Swammerdam[1366]. Most of his tribes indicate natural groups of greater or less value: but some of his larger groups are artificial, as you will see by the mere inspection of the table.
INSECTA
Ametamorphota
Apoda Terrestia[1367]. Aquatica.
Pedata
Hexapoda
Terrestia[1368] Majora[1368]. Minora[1369].
Aquatica[1370].
Octopoda Caudata[1371]. Non caudata[1372].
14-poda.
24-poda.
30-poda.
Polypoda
Terrestia Cylindrica[1373]. Compressa[1374].
Aquatica[1375] Corpore tereti. ------ plano. Bicaudata.
Metamorphumena
Metamorphosis semicompleta[1376] Orthoptera. Heteroptera. Homoptera. Libellulina. Ephemerina.
Metamorphosis incompleta vel obtecta
Coleoptera.
Anelytra
Alis farinaceis[1377].
Alis membranaceis
Diptera.
Tetrapter
Gregaria et Favifica Mellifica[1378]. Non Mellifica[1379].
Solitaria non Gregaria et Favifica
Apiformia[1380].
Vespiformia Breviora[1381]. Augustiora[1382].
Papilioniformia[1383].
Seticaudæ, seu Tripilia[1384].
Metamorphosis coarctata Muscidæ et Ichneumones minuti L.[1385]
This era produced several great and original geniuses, who enriched the science with a vast increment of real knowledge. The illustrious Zoologists whose names it bears,--the one by his dissections and anatomical researches, and the other by his concise and well drawn descriptions of numerous insects, by various interesting observations on their manners and characters, and by the purity of his latinity,--contributed greatly to its progress towards perfection. Leeuwenhoek also, the compatriot of Swammerdam, and Hooke of Ray, amongst other objects submitted to their powerful microscopes, did not neglect insects.--To the former we are indebted for the remarkable discovery that the flea belongs to those that undergo a metamorphosis. Ray had besides two coadjutors whose names ought not to be forgotten,--Willughby and Dr. Martin Lister. The former is characterized by his lamenting friend as one of the profoundest of naturalists, as well as one of the most amiable and virtuous of men. What advantage Entomology would have reaped from his labours may be inferred from the eminent services that he rendered that science, amongst other branches of Zoology, during his short life. It appears from Ray's Letters[1386], that he drew up a history of insects and exsanguia, which probably formed the groundwork of the posthumous Historia Insectorum of that author; concerning which he says, "The work which I have now entered upon is indeed too great a task for me: I rely chiefly on Mr. Willughby's discoveries and the contributions of friends[1387]." And indeed Willughby's name and initials occur so frequently in that work, that it may be esteemed their joint production. Lister by his various writings elucidated many points relating to insects; and he may be regarded as the first modern who observed that spiders can sail in the air. But the most important of his works, and that on which his fame as an Entomologist is principally founded, is his admirable treatise De Araneis; in which his systematic arrangement of these animals leaves far behind all former attempts, and rivals that of the best modern Arachnologists. His specific descriptions are drawn with a precision till then unknown; and each is headed by a short definition of the species, which he calls the Titulus, synonymous with the Nomen specificum of Linné, whose canon of twelve words it rarely exceeds.
One of the most important events of this era was the complete exposure and refutation of the absurd doctrine of equivocal generation, which had maintained its ground in the schools of philosophy from the time of Aristotle. Our own immortal Harvey was the first who dared to controvert this irrational theory: and his dictum--Omnia ex ovo--was copiously discussed and completely established by two of the ablest physiologists that Italy has produced, Redi and Malpighi.
Previously to the publication of the Historia Insectorum, no other works of eminence, with the exception of Madam Merian's beautiful illustration of the metamorphosis of the insects of Surinam, made their appearance: but in the interval of twenty-five years, which elapsed between the publication of that work and of Linné's first outline of his Systema Naturæ, Entomologists became more numerous and active. In England the pious and learned author of the Physico and Astro-Theology was celebrated for the assiduity with which he studied insects; and in the former of these works has concentrated a vast number of interesting observations connected with their anatomy and history. No Englishman contributed more to the progress of Natural History, both as a writer and collector, than that disinterested physician and naturalist Sir Hans Sloane, whose extensive and valuable library and well-stored cabinets formed the original nucleus of the present vast collection of the British Museum. Amongst other departments, that of insects was not overlooked by him; and it is to be regretted that those which he had accumulated have either perished from neglect or are not accessible. Other Entomologists were eminent at this period in Britain. The principal of these were Petiver, Dale (to whom Ray bequeathed his collection of insects), Bobart, Bradley, and Dandridge; the last of whom, as Bradley tells us, delineated and described 140 species of spiders.
I must not omit here to observe that our ROYAL SOCIETY, the origin of which took place in this era, communicated a new and powerful impulse to the public mind in favour of Physical Science, and greatly accelerated the progress of Natural History. It acted not only as a centre of excitement which stimulated to exertion, but also as a focus to collect the scattered rays of light before they were dissipated. Insulated observations in every department of nature were thus preserved; and communications from the most eminent naturalists in various parts of Europe ornamented its Transactions. So that from the establishment of this illustrious Society, the triumphant march of Physical Science of every kind towards its acme may be dated.
4. Era of Linné, or of the Alary System. We are now arrived at that period in the history of Natural Knowledge, especially of Entomology, in which it received that form, with respect to its general outline, which, amidst many lesser mutations, has been preserved ever since. Swammerdam had altogether deserted the system of Aristotle, and Ray mixed it with that of his predecessor. But a brilliant star soon appeared in the North[1388], which was destined to be the harbinger of a brighter day than had ever before illuminated the path of the student of the works of God. The illustrious philosopher whose name distinguishes this new era, imbibed a taste for Entomology almost as early as for Botany[1389]; and though the latter became his favourite, and absorbed his principal attention, he did not altogether neglect the former. In the first edition of his Systema Naturæ, published in 1735, and contained in only fourteen folio pages[1390], he began to arrange the three kingdoms of nature after his own conceptions. But this initiatory sketch, as might be expected, was very imperfect; and with respect to insects, instead of an improvement upon his predecessors, was extremely inferior to what Ray had effected; for he puts into one Order (to which he gives the name of Angioptera) the Lepidoptera, Neuroptera, Hymenoptera, and Diptera. In this work, however, Generic Characters were first given. In successive editions he continued to improve upon this outline: in the fourth he finally settled the number and denominations of his Orders; and in the twelfth (uniting the Orthoptera, which he had at first considered as of a Coleopterous type, to the Hemiptera) also their limits. His system, being founded upon the absence or presence and characters of the organs for flight, is in some degree a republication of the Aristotelian, and may be called the Alary System.
{ { Superior { crustaceous with a straight Coleoptera 1. { { { suture { { { semicrustaceous, incumbent Hemiptera 2. { 4.{ { imbricated with Lepidoptera 3. { { { scales Wings { { All { membranous-- { unarmed } Neuroptera 4. { { Anus { aculeate } Hymenoptera 5. { 2. Poisers in the place of the Diptera 6. { posterior pair { 0. Or without either wings or Aptera 7. { elytra
In considering this table, it must strike every one acquainted with the subject, that although the assumption of a single set of organs whereon to build a system can scarcely be expected to lead to one perfectly natural, yet that the majority of the groups here given as Orders merit that character. The second indeed and the last require further subdivision, and concerning the fourth no satisfactory conclusion has yet been drawn. With regard to his series of the Orders, it is mostly artificial. Linné has the advantage of all his predecessors in giving clearer definitions of his Orders, and in their nomenclature; in which he has followed the path first trodden by Aristotle.
One of his most prominent excellencies, which led the way more than any thing else to a distinct knowledge of natural objects, was his giving definitions of his genera, or the groups that he distinguished by that name, since all preceding writers had merely made them known by the imposition of a name. His generic characters of insects were of two kinds: A shorter, containing the supposed essential distinction of the genus, given at the head of the Class; and another, generally longer, and including non-essentials, given at the head of the Genus. The first he denominated the essential, and the latter the factitious or artificial character. He did not do for insects what he did for Botany,--draw up what he has called the natural character of a genus, which included both the others, and noticed every other generic distinction[1391].
The older Naturalists used to treasure in their memories a short description of each species, by which when they wished to speak or write of it they made it known. Thus, in speaking of the common lady-bird they would call it "the Coccinella with red coleoptra[1392] having seven black dots." This enunciation of any object was at first called its Title (Titulus), and afterwards its Specific Name (Nomen specificum), and by Linné was restricted to twelve words[1393]. But as the number of species increased to remember each definition was no easy task; that he might remedy this inconvenience, he invented what is called the Trivial Name (Nomen triviale), which expressed any species by a single term added to its generic appellation, as Coccinella septem-punctata; and thereby conferred a lasting benefit on Natural History. This convenient invention has rendered it less necessary to restrict the Nomen specificum to twelve words: it is desirable, however, that the definition of a species should be as short as possible, and contain only its distinctive characters. In his definitions and descriptions Linné was often very happy; but sometimes, in studying to avoid prolixity, he forgets Horace's hint,
... "Brevis esse laboro Obscurus fio--"
and makes his definitions of species, without adding a description, so extremely short as to suit equally well perhaps a dozen different insects. The minor groups into which he has divided some of his Orders and Genera are sometimes natural, sometimes artificial. Those of the Coleoptera, from characters drawn from their antennæ (as is evident from his arrangement of the genera in that Order), are of the latter description; while those of his Aptera are more natural. The genera that he has most happily laboured in this respect are his Hemipterous ones of Gryllus, Cicada, and Cimex, and all his Lepidoptera. He had such a tact for discovering natural groups in general, that in him it seems almost to have been intuitive.
But in no respect were the labours of Linné more beneficial to the science and to Zoology in general, than when he undertook to describe the animals of his own country. His Fauna Suecica is an admirable exemplar, which ought to stimulate the Zoologists of every country to make it one of their first objects that its animal productions shall no longer remain unregistered and undescribed. Botanists have almost every where been diligent in effecting this with respect to plants, but other branches of Natural History have been more neglected. In his Systema Naturæ Linné attempted this for all the productions of our globe. The idea was a vast one; and the execution, though necessarily falling far short of it, did him infinite honour: and in it he has laid a foundation for his successors to build upon till time shall be no more.
Such were the services rendered to Entomology by the labours of the immortal Swede; services so extensive as well as eminent, that had they been the fruit of a whole life devoted to this single object, they would have entitled him to a high rank amongst the heroes of the science. But how much more astonishing are they when considered but as gleanings from his hours of relaxation, snatched from labours infinitely greater, the produce, as he himself tells us, of moments consumed by others in "venationibus, confabulationibus, tesseris, chartis, lusibus, compotationibus[1394]." It is not so much in original discovery that the merits of Linné lie,--though considered in this view they are pre-eminent,--as in the unrivalled skill with which he sifted the observations of his predecessors, separating the ore from the dross, and concentrating scattered rays of light into one focus.
This era produced other systematists who adopted various methods, but none that merit particular notice except Geoffroy and De Geer. The former in this view is principally celebrated as the author of the method generally adopted by modern Entomologists, of dividing the Coleoptera into primary sections, according to the number of the joints of their tarsi. This method, though in many instances, as was formerly observed[1395], it leads to artificial results, in others affords a clue to natural groups; it can only therefore be applied subject to frequent exceptions. Geoffroy's work[1396], which was published in 1764, was further serviceable by indicating many genera not defined by Linné.
GENERAL ORDERS. CLASSES. CLASSES. {I. Wings covered { with scales. Tongue { spiral. { LEPIDOPTERA. { {II. Wings membranous, { naked. Mouth { without teeth or tongue. { TRICHOPTERA. { EPHEMERINA. { {III. Wings membranous, {I. Four Wings { equal, reticulated. { without { Mouth with teeth. { wing-cases { Rest of { { NEUROPTERA. { { { {IV. Wings membranous { { unequal, nervures mostly { { longitudinal. Mouth { { with teeth. A sting { { or borer in the { { female. { { HYMENOPTERA. { { { {V. Wings membranous. { { Tongue bent under { { the breast. { { HOMOPTERA Leach. { { {VI. Elytra half { { coriaceous and half { { membranous, crossed. A pair { { of membranous wings. { { Tongue bent under the { { breast. HEMIPTERA {II. Two Wings { Leach. { covered by { {I. Having { two {VII. Elytra coriaceous { wings { wing-cases { or semicrustaceous, { { { aliform. A pair of { { { membranous wings. { { { Mouth with teeth. { { { ORTHOPTERA. { { { { { {VIII. Elytra hard and { { { crustaceous. A pair of { { { membranous wings. { { { Mouth with teeth. { { { COLEOPTERA. { { { { {IX. A pair of membranous INSECTS { { { wings. A pair of { { { poisers. Mouth { { { with a tongue without { { { teeth. DIPTERA. { { { { {III. Two Wings {X. A pair of membranous { { uncovered { wings. No { { poisers, tongue, { { or teeth in the male. { { No wings but a tongue { { in the breast of the { { female. COCCUS L. { { {IV. Undergoing {XI. No wings. Six legs. { { a { Mouth with a tongue. { { metamorphosis { APHANIPTERA. { { {II. Without { {XII. No wings. Six legs. { wings { { Head and Trunk { { distinct. HEXAPOD { { APTERA, TERMES, { { PSOCUS. { { { {XIII. No wings. 8 or {V. Undergoing { 10 legs. Head { no { united to the trunk. { metamorphosis { OCTOPOD APTERA, { ARACHNIDA, { CRUSTACEA. { {XIV. No wings. 14 { Legs or more. Head { separated from the trunk. { POLYPOD APTERA. { CRUSTACEA.
We next come to one of the greatest names in Entomology, the celebrated De Geer, who united in himself the highest merit of almost every department of that science. Both as a systematist, anatomist, and physiologist, and as the observant historian of the manners and economy of insects, his Mémoires pour servir à l'Histoire des Insectes are above all praise. His system[1397] is contained in a posthumous volume published in 1778[1398].
This system, though built upon the instruments of flight; in its ternary groups, equivalent to the Orders of Linné, adds likewise the instruments of manducation, and is thus intermediate between that of Linné and Fabricius, who perhaps from the consideration of it might derive the first idea of assuming the last-mentioned organs as the basis of a new method. But, though partaking of both, it is nearer to nature than either; and had its illustrious author laid less stress upon the number and substance of the organs of flight, it would probably have been as near perfection in this respect as most that have succeeded it. But following too strictly these characters, he has been led to place in different Classes, or rather Orders, insects that ought not to have been so separated,--as in the case of the two sections of the Hemiptera, and the Coccidæ. In other respects the whole of De Geer's Mémoires are a storehouse of valuable observations, in which he has furnished many a clue for threading the labyrinth of nature, and given most complete and interesting histories of the whole economy and habits of many tribes and genera,--as of the Trichoptera, Aphides, Ephemerina, &c.
In this latter department of the science a light shone during part of the era we are now considering, which eclipsed every one that appeared before it, and has scarcely been equalled by any one that succeeded it. The date of its first appearance, indeed, was a year before that of Linné's first outline of his Systema Naturæ before alluded to; but it may properly be regarded as belonging to his era, since it did not disappear till some years after that had begun. A volume indeed would scarcely suffice to do justice to the preeminent merits of Reaumur, as exhibited in his admirable Mémoires pour l'Histoire des Insectes[1399]: I must therefore content myself with observing, that in judgement and ingenuity in planning his experiments; in patient assiduity in watching their progress; in the elegance of his language, and the felicity of his illustrations, he has rarely, if ever, been equalled. Every subject that he undertook was thoroughly investigated, and in the true spirit of philosophical inquiry. Every where you see him the same unprejudiced and profound observer, attached to no system, anxious only for truth and the advancement of science. If he has any fault, it is, perhaps, that of being sometimes too prolix; but we must recollect that from the nature of his subject much diffuseness was often necessary to render his meaning clear. A greater objection is his total inattention to all system, except with regard to Lepidoptera and their larvæ[1400], so that it is often difficult to ascertain the insects whose history he gives. But with these exceptions, no observer of nature, who wishes his discoveries to be at once profound and interesting, can copy a better model or one nearer to perfection.
Next to that of Reaumur, the name of his admiring correspondent Bonnet may be mentioned. This great physiologist, though still more deficient in systematical knowledge[1401], was also an admirable observer of the economy and manners of insects. In this sense he became an Entomologist before he was seventeen years of age, in consequence of an impression made upon him by the account of the Antlion in that attractive work the Spectacle de la Nature. From verifying its wonderful history with his own eyes, he entered with enthusiasm upon the study of other insects, his observations on which he regularly communicated to Reaumur. Amongst other interesting inquiries, his experiments on that singular anomaly in nature the generation of Aphides[1402] do him the highest credit, and have set that question perfectly at rest[1403].
In another department of the science this period was distinguished by a work which may almost be deemed a prodigy. I am speaking of Lyonet's admirable treatise on the anatomy of the caterpillar of the Cossus,--a work which will uphold his reputation as long as Entomology shall be cultivated as a science, or the comparative Anatomist be delighted to trace the footsteps of Divine Wisdom in the gradually varying structure of animals. The plates to this publication, executed by the hand of its excellent author, are as wonderful as the work itself; and together, to use Bonnet's words, form a demonstration of the existence of GOD. It is infinitely to be regretted that the author of this incomparable monument of scientific ardour and patient industry should have died before the full completion of his anatomical description of the pupa and imago of the same insect; of which he had prepared a considerable portion of the manuscript, and engraved upwards of twenty of the plates[1404].
Numerous other writers in various departments of the science appeared during this era; but it would be useless to enter into a particular detail of their works and merits. I cannot however omit noticing, on account of his inimitably accurate and chastely coloured representations of Lepidoptera, Sepp's beautiful Nederlandsche Insecten, in which the whole history of these animals, from the egg to the fly, is described and portrayed. In our own country this era was distinguished by no entomological work of any great eminence. Albin, Wilks, and Harris produced the principal. Gould, however, without having any thing of system, gave an admirable account of English ants, which I formerly noticed[1405].
One of our first poets, the celebrated Gray, was also much devoted to Entomology. From his interleaved copy of the Systema Naturæ, that venerable and able naturalist, Sir T. G. Cullum, Bart. copied the following characters of the genera of insects of Linné, drawn up in Latin Hexameters, which he kindly communicated to me.
COLEOPTERA.
Alas lorica tectas Coleoptera jactant.
*
Serra pedum prodit Scarabæum et fissile cornu. Dermesti antennæ circum ambit lamina caulem Qui caput incurvum timidus sub corpore celat. In pectus retrahens caput abdit claviger Hister. Occiput Attelabi in posticum vergit acumen. Curculio ingenti protendit cornua rostro. Silpha læves peltæ atque elytrorum exporrigit oras. Truncus apex clavæ, atque antennulæ Coccionellæ.
**
Cassida sub clypei totam se margine condit. Chrysomela inflexa loricæ stringitur ora. Gibba caput Meloë incurvat thorace rotundo. Oblongus frontem et tenues clypei exerit oras Tenebrio. Abdomen Mordellæ lamina vestit. Curta elytra ostentat Staphylis caudamque recurvam.
***
Tubere cervicis valet, antennisque Cerambyx. Pectore Leptura est tereti corpusque coarctat. Flexile Cantharidis tegmen, laterumque papillæ. Ast Elater resilit sterni mucrone supinus. Maxillâ exsertâ est oculoque Cicindela grandi. Bupresti antennæ graciles, cervice retractâ. Nec Dytiscus iners setosâ remige plantâ. Effigiem cordis Carabus dat pectore trunco. Necydalis curto ex elytro nudam explicat alam. Curtum, at Forficulæ tegit hanc, cum forcipe cauda.
HEMIPTERA.
Dimidiam rostrata gerunt Hemiptera _crustam Fœmina serpit humi interdum, volat æthera conjux._
Depressum Blattæ corpus venterque bicornis. Dente vorax Gryllus deflexis saltitat alis. Rostro Nepa rapax pollet chelisque. Cicada Fastigio alarum, et rostrato pectore saltat. Tela Cimex inflexa gerit, cruce complicat alas. Notonecta crucem quoque fert remosque pedales. Cornua Aphis caudæ et rostrum, sæpe erigit alas. Deprimit has Chermes, dum saltat pectore gibbo. Coccus iners caudæ setas, volitante marito. Thrips alas angusta gerit, caudamque recurvam.
LEPIDOPTERA.
Squamam alæ, linguæ spiram Lepidoptera jactant.
Papilio clavam, et squamosas subrigit alas. Prismaticas Sphinx antennas, medioque tumentes: At conicas gravis extendit sub nocte Phalæna.
NEUROPTERA.
Rete alæ nudum atque hamos Neuroptera caudæ.
Dente alisque potens secat æthera longa Libella. Caudâ setigerâ erectis stat Ephemera pennis. Phryganea elinguis rugosas deprimit alas. _Hemerinus_que bidens planas tamen explicat ille. Et rostro longo et caudâ Panorpa minatur. Raphidia extento collo setam trahit unam.
HYMENOPTERA.
At vitreas alas, jaculumque Hymenoptera _caudæ. Fœmineo data tela gregi, maribusque negata._
Telum abdit spirale Cynips, morsuque minatur. Maxillas Tenthredo movet, serramque bivalvem. Ichneumon gracili triplex abdomine telum: Et valde aurato resplendet corpore Chrysis. Haurit Apis linguâ incurvâ, quod vindicat ense. Sphex alam expandit lævem, gladiumque recondit. Alæ ruga notat Vespam, caudæque venenum. Squamula Formicam tergi, telumque pedestrem, Dum minor alata volitat cum conjuge conjux. Mutilla impennis, sed cauda spicula vibrat.
DIPTERA.
Diptera sub geminis alis se pondere librant.
Os Œstro nullum, caudâque timetur inermi. Longa caput Tipula est, labiisque et prædita palpis. Palpis Musca caret, retrahitque proboscida labris. Qua Tabanus gaudet pariter, palpis subacutis. Os Culicis molli e pharetrâ sua spicula vibrat. Rostrum Empis durum et longum sub pectore curvat. Porrigit articuli de cardine noxia Conops. Porrigit at rectum et conicum sitibundus Asilus. Longum et Bombylius qui sugit mella volando. Unguibus Hippobosca valet, vibrat breve telum.
APTERA.
Aptera se pedibus pennarum nescia jactant.
Exit tres setas cauda extendente Lepisma. Saltatrix est cauda Poduræ inflexa bifurca. Armantur Termis maxillis ora duabus. Fert telum quod ab ore Pediculus edat acutum. Pulicis inflexum rostrum est, telumque recondit. Octo Acarus pedibus duplicique instructus ocello est. Lumina bis bina octipedata Phalangia gestant. Octo oculis totidem pedibusque se Aranea jactat. His etiam adjungit chelatos Scorpio palpos. Dena pedum natura dedit fulcimina Cancro. Unoculo bissena (duosque ambobus ocellos). Quorum his chelatos gerit, ille gemellos. Ovalis pedibus bis septem incedit Oniscus. Innumeris pedibus Scolopendra angusta movetur. Secernit reliquis structura cylindrica Iulum.
During this era, and by the influence of Linné, in the year 1739 the Royal Academy of Sciences at Stockholm was established, which did for Natural History in Sweden what our own Royal Society had done for it in England. Other societies, with a similar object, were formed in different parts of Europe, and were attended by similar good effects. At Paris, at Berlin, at St. Petersburg, at Moscow, at Turin, at Lisbon, &c., the lovers of Nature, at that time and subsequently, have associated for this purpose; and I may mention here, that I may not revert to the subject, the great Natural History association of our own country, THE LINNEAN SOCIETY, named after the illustrious Swede, which was first instituted in 1788, and incorporated by royal charter in 1802. In the Transactions of this learned body, the Zoologist in general, and particularly the Entomologist, will find much useful information and many interesting observations connected with his science. This flourishing society consists at this time of above 600 members, of whom more than 500 are Fellows;--a gratifying proof how widely Natural History is cultivated in the British Empire[1406].
5. Era of Fabricius, or of the Maxillary System.--We are now arrived, if its consequences be considered, at one of the most important epochs of the science. Fabricius, a pupil of Linné, who highly estimated his entomological acquirements[1407], thinking that the system of his master was not built upon a foundation sufficiently fixed and restricted[1408], conceived the idea of doing for Entomology what the latter had done for Botany. As the learned and illustrious Swede had assumed the Fructification for the basis of his system in that science, so the emulous and highly-gifted Dane, observing how happily those organs were employed as characters in extricating the genera of Vertebrate animals, assumed the instruments of manducation, far more numerous and various in insects, for the basis of a new system of Entomology; which, from the maxillæ being principally employed to characterize the Classes or rather Orders, may be called the Maxillary System. De Geer, indeed, as we have seen above, had, in the majority of his Classes, to the organs of flight added the parts of the mouth: but Fabricius pursued the idea much further, and made the Trophi[1409], or Instrumenta Cibaria as he called them, the sole corner-stone of his whole superstructure. Though nothing seems to have been further from his intention than to follow Nature, since he complains that Linné by following her too closely had lost the Ariadnean thread of system[1410], yet it is singular that, by building upon this seemingly narrow foundation, he has furnished a clue, by the due use of which, instead of deserting her, his successors have been enabled with more certainty to extricate her groups: since the parts in question being intimately connected with the functions and economy of these animals, where they differ materially, indicate a corresponding difference in their character and station.
The first outline of his System, I believe, appeared in his Systema Entomologiæ published in 1775; and the last, in his Supplement to his Entomologia Systematica in 1798. In this the series and characters of his Classes (for so, after De Geer, he denominates his primary groups) were as follows:--
*
1. ELEUTHERATA[1411]. (Coleoptera L.) Maxilla naked, free, palpigerous.
2. ULONATA[1412]. (Orthoptera Oliv.) Maxilla covered by an obtuse galea or lobe.
3. SYNISTATA[1413]. (Neuroptera L., excluding the Libellulina, and taking in Termes L. and Thysanura Latr.) Maxilla geniculate at the base and connate with the labium.
4. PIEZATA[1414]. (Hymenoptera L.) Maxilla corneous, compressed, often elongate.
5. ODONATA[1415]. (Libellulina M^cL.) Maxilla corneous, toothed, two palpi.
6. MITOSATA[1416]. (Myriapoda Leach.) Maxilla corneous, vaulted, not palpigerous.
**
7. UNOGATA[1417]. (Pulmonary Arachnida Latr.) Maxilla corneous, armed with a claw.
***
8. POLYGONATA[1418]. (Isopod and Branchiopod Crustacea Latr.) Palpi mostly six; Maxillæ many within the labium.
9. KLEISTOGNATHA[1419]. (Brachyurous Decapod Crustacea Latr.) Many Maxillæ without the labium, closing the mouth.
10. EXOCHNATA[1420]. (Macrurous Decapod Crustacea Latr.) Maxillæ many without the labium, covered by palpi.
****
11. GLOSSATA[1421]. (Lepidoptera L.) Mouth with a spiral tongue between reflexed palpi.
12. RYNGOTA[1422]. (Hemiptera Latr.) Mouth with a rostrum, having a jointed sheath.
13. ANTLIATA[1423]. (Diptera L., Anoplura Leach., Trachean Arachnida Latr. &c.) Mouth with a haustellum without joints.
The Orders of Fabricius are equivalent usually to the primary groups of the Linnean Orders, and are regulated chiefly by the antennæ.
In estimating the value of the above system, we must bear in mind that, according to the statement of its author, it was intended to be partly artificial and partly natural: artificial as to its Classes and Orders; natural as to its genera, species, and varieties[1424]. He admitted, however, that natural Classes, &c. do exist; but he contended that artificial ones should be substituted for them, till further discoveries had cleared the way for their satisfactory development[1425]. As therefore his system, in its primary and secondary groups, was confessedly artificial, and the only use of an artificial system being to facilitate the study of any department of Natural History, its value must be estimated by the facilities it affords to the entomological student. But here, it must be allowed, that instead of enlarging the entrance to the temple of his science, it has made it narrower, and has placed most discouraging impediments in his way.
If you examine the definitions of his Classes, you will find them in a variety of cases calculated rather to mislead than to instruct a learner. Thus that of the Eleutherata would equally well suit the Piezata and several others: that of the Piezata is scarcely to be found in it; since in this the maxilla, instead of being corneous, is usually coriaceous[1426], and its lobe sometimes nearly membranous. In the Unogata he even mistakes the mandibles for maxillæ. Let any young Entomologist endeavour to make out the Fabrician class of a Cicindela for instance; and finding its maxillæ corneous and armed with a claw, he would conclude that it belonged to the Unogata rather than to the Eleutherata. Besides all this, the necessity of examining minute parts not easily come at without dissection, is very discouraging to a beginner.
From hence it is evident, that the system of Fabricius, considered as an artificial one or a method, was no improvement upon the classification of his master Linné, but rather a retrograde movement in the science.
As to that part of his system in which he professes to take nature for his guide, his genera,--though even with respect to them he seems fearful of following her too closely[1427],--he certainly has rendered most essential services to Entomology, and laid the foundation of all that has since been done for its improvement. But it must be observed, that the series of his genera is often altogether artificial; as where he separates and places far asunder the Saprophagous and Thalerophagous Petalocerous beetles.
Entomology, however, in other respects was deeply indebted to this great man. He first, as was lately observed, directed the attention of her votaries to parts which enabled them better to follow the chain of affinities, and to trace out natural groups. In his Philosophia Entomologica, drawn up on the plan of Linné's Philosophia Botanica, he bequeathed to the science a standard work that ought to be studied by every Entomologist. His incredible labours in defining new genera and describing new species, with which view he travelled into various parts of Europe, and seven times into Britain, have been of infinite service[1428], and placed the science upon a footing much nearer to that of Botany than it had ever before attained.
6. Era of Latreille, or of the Eclectic System. The system of Fabricius, though generally adopted in Germany and Switzerland, did not meet with a universal reception. It seems to have gained no permanent footing in the North of Europe, Britain, or France. In the latter country the Linnean phraseology and characters of the Orders were retained by the celebrated Olivier; while at the same time his definitions of genera were constructed, after the Fabrician model, upon the antennæ and the oral organs. But a new and brilliant genius had now appeared in France, whose indefatigable labours and singular talents have thrown more light over entomological science than those of all his predecessors. In 1796, about two years after Fabricius had completed his Entomologia Systematica emendata et aucta, M. Latreille published his Précis de Caractères Génériques des Insectes; in which important work, walking in the steps of his great compatriot Bernard de Jussieu, he disregarded all artificial systems of Entomology, and attempted to construct one upon a natural basis: and to this end, uniting the consideration of the instruments of manducation with that of the organs for flight and motion, and of other external characters,--or the system of Linné with that of Fabricius,--he became the founder of the modern or Eclectic system[1429]; for he judiciously adopted that sensible dictum of Scopoli, "Classes et Genera naturalia, non sola instrumenta cibaria, non solæ alæ, nec solæ antennæ constituunt, sed structura totius, ac cujusque vel minimi discriminis diligentissima observatio[1430]." His object has been in the above and subsequent works, by dividing his Classes into natural Groups, from the Order to the Genus, to trace out in all its windings, to its inmost recesses, the perplexing labyrinth of the true system of the CREATOR:--of what he has effected, the subjoined tables will give you a sufficient idea[1431].
1817.
Entoma
CLASS: I. Crustacea.
CLASS: II. Arachnida
ORDER: Pulmonariæ
FAMILY: Araneides
Sedintariæ TRIBE: Territelæ. TRIBE: Tubitelæ. TRIBE: Inequitelæ. TRIBE: Orbitelæ. TRIBE: Laterigradæ.
Vagantes TRIBE: Citigradæ. TRIBE: Saltigradæ.
FAMILY: Pedipalpæ.
FAMILY: Scorpioides.
ORDER: Tracheariæ
FAMILY: Pseudoscorpiones.
FAMILY: Holetra
TRIBE: Phalangita.
TRIBE: Acaridia SUBTRIBE: Trombidites. SUBTRIBE: Riciniæ. SUBTRIBE: Hydrachnellæ. SUBTRIBE: Microphthiræ.
CLASS: III. Insecta
ORDER: 1. Myriapoda FAMILY: Chilognatha. FAMILY: Chilopoda.
ORDER: 2. Thysanura FAMILY: Lepismenæ. FAMILY: Podurellæ.
ORDER: 3. Parasita FAMILY: Mandibulata. FAMILY: Edentula.
ORDER: 4. Suctoria.
ORDER: 5. Coleoptera.
ORDER: 6. Orthoptera.
ORDER: 7. Hemiptera.
ORDER: 8. Neuroptera.
ORDER: 9. Hymenoptera.
ORDER: 10. Lepidoptera.
ORDER: 11. Rhiphiptera.
ORDER: 12. Diptera.
1825
Hyperhexapi.
CLASS: I. Crustacea.
CLASS: II. Arachnides.
ORDER: Pulmonariæ
FAMILY: Pedipalpi TRIBE: Scorpionides. TRIBE: Tarentulæ.
FAMILY: Araneides
SECTION: Tetrapneumones.
SECTION: Dipneumones. TRIBE: Tubitelæ. TRIBE: Inæquitelæ. TRIBE: Orbitelæ. TRIBE: Laterigradæ. TRIBE: Citigradæ. TRIBE: Saltigradæ.
ORDER: Tracheariæ FAMILY: Pycnogonides. FAMILY: Pseudoscorpiones. FAMILY: Phalangita. FAMILY: Acarides. FAMILY: Hydrachnellæ. FAMILY: Riciniæ. FAMILY: Microphthira.
CONDYLOPA.
CLASS: III. Myriapoda.
ORDER: Chilognatha FAMILY: Anguiformia. FAMILY: Penicillata.
ORDER: Chilopoda FAMILY: Inæquipedes. FAMILY: Æquipedes.
CLASS: Aptera.
ORDER: Thysanoura FAMILY: Lepismenæ. FAMILY: Podurellæ.
ORDER: Parasita FAMILY: Mandibulata. FAMILY: Siphunculata.
ORDER: Siphonaptera.
Hexapoda.
CLASS: IV. Insecta.
CLASS: Alata ORDER: Coleoptera } ORDER: Orthoptera }FAMILY:Elytroptera. ORDER: Hemiptera }
ORDER: Neuroptera } ORDER: Hymenoptera }FAMILY:Anelytra quadripennia. ORDER: Lepidoptera }
ORDER: Rhiphiptera }FAMILY:---------- bipennia. ORDER: Diptera }
Having given you these tables of the Orders, from a comparison of which you will be able to trace the improvements in his system made by this learned Entomologist in the interval of eight years, I shall proceed to give those of his subordinate groups arranged under each. This I have already done, to save space, in the Arachnida and Insecta aptera.
Column Key: A = ORDER. B = SECTION. C = FAMILY. D = SUBFAMILY. E = TRIBE. F = SUBTRIBE.
A. B. C. D. E. F.
{Cicindeletæ. {Terrestres { {Truncatipennes. { { {Bipartiti. {Adephagi { {Carabici {Thoracici. { { {Abdominales. { { {Subulipalpi. { {Aquatica {Hydrocanthari. { {Gyrinites. { { {Fissilabres. {Brachyptera {Longipalpi. { {Depressi. { {Microcephali. { { {Sternoxi {Buprestides. {Serricornes{ {Elaterides. {Pentamera { { { { { {Cebrionites. { { { {Lampyrides. { { {Malacodermi{Melyrides. { { {Clerii. { { {Xylotragi. { { {Ptiniores. { { { { {Histeroida. { { {Peltoides. { { {Palpatores. { {Clavicornes {Dermestini. { { {Byrrhii. { { {Macrodactyli. { { { {Palpicornes {Hydrophilii. Coleo-{ { {Sphæridiota. ptera.{ { {Coprophagi. { { {Arenicolæ. { { {Xylophili. { { {Scarabæides {Phyllophagi. { {Lamellicornes { {Anthobii. { { {Melitophili. { {Lucanides. { { {Pimeliariæ. { {Melasoma {Blapsides. { { {Tenebrionites. { { { { {Dioperiales. { {Taxicornes {Cossyphenes. { { {Crassicornes. {Heteromera{ { {Helopii. { {Cistelides. {Stenelytra {Securipalpi. { {Œdemerites. { {Rhyncostoma. { { {Lagriariæ. { {Pyrochroides. {Trachelides {Mordellonæ. {Anthicides. {Horiales. {Cantharidiæ.
ORDER. SECTION. FAMILY. TRIBE.
{Bruchelæ. {Anthribides. {Rhynchophora {Altelabides. { {Brentides. { {Curculionites. { { {Scolitarii. {Xylophagi {Bostrichini. { {Paussili. { {Trogossitarii. {Platysoma. {Tetramera { {Prionii. { { {Cerambycini. { {Longicornes {Necydalides. { { {Lamiariæ. { { {Lepturetæ. { { { {Eupoda {Sagrides. Coleoptera { { {Criocerides. { { { { {Cassidariæ. { {Cyclica {Chrysomelinæ. { {Galerucidæ. { {Clavipalpi. {Trimera {Aphidiphagi. { {Fungicolæ. { {Pselaphii. {Monomera. {Forficularia. {Blattariæ. { I. {Mantides. { {Spectra. Orthoptera { { II. {Gryllides. { {Locustariæ. { { III. {Acridites. {Longilabra. {Membranaceæ. {Geocorisæ {Nudicolles. { {Oculatæ. {Heteroptera { {Ploteres. { { { {Hydrocorisæ {Nepides. { {Notonectides. Hemiptera { { {Stridulantes. { {Cicadariæ {Fulgorellæ. { { {Membracides. { { {Cicadellæ. { { {Homoptera { {Psyllides. {Hymenelytra {Physapi. { {Aphidii. {Gallinsecta.
ORDER. SECTION. FAMILY. TRIBE. SUBTRIBE.
{Subulicornes {Libellulina. { {Ephemerina. {Panorpatæ. Neuroptera { {Myrmeleonides. { {Hemerobini. { {Planipennes {Psoquillæ. {Filicornes { {Termitinæ. { {Raphidinæ. {Plicipennes. {Semblides. {Perlides.
{Securifera {Tenthredinetæ. { {Urocerata. { {Terebrantia { {Evaniales. { { {Ichneumonides. { { {Gallicolæ. { {Pupivora {Chalcidites. { {Chrysides. { {Oxyuri. { { {Heterogyna {Formicariæ. Hymenoptera { { {Mutillariæ. { { { { {Scolietæ. { { {Sapygites. { { {Pompilii. { {Fossores {Sphegides. { { {Bembecides. { { {Larratæ. {Aculeata { {Nyssonii. { {Crabronites. { {Diploptera {Vespariæ. { {Masarides. { { {Andrenetæ. { { {Solitariæ. {Mellifica { {Andrenoides. { {Dasygastræ. {Apiariæ {Cuculinæ. {Scobulipedes. {Sociales.
{Hexapoda. {Papilionides{Perlata. {Diurna { {Argus. { {Hesperides. { { {Hesper-sphinges. {Crepuscularia {Sphingides. Lepidoptera { {Zygænides. { { {Bombycites. { {Pseudo-Bombyces. { {Tineites. { {Noctuælites. {Nocturna {Tortrices. {Phalænites. {Crambites. {Pterophorites.
ORDER. SECTION. FAMILY. TRIBE. SUBTRIBE.
{Culicides. {Culiciformes. {Nemocera { {Gallicolæ. { {Tipulariæ {Terricolæ. { {Fungivoræ. { {Tabanii. {Florales. { {Sicarii. { {Mydasi. { {Leptides. { {Dolichopoda. { I. {Tanystoma {Asilici. { { {Hybotina. { { {Empides. { { {Anthracii. { { {Bombyliarii. { { {Vesiculosa. { { Diptera { {Notacantha {Xylophagei. { { {Stratyomides. { { { { {Syrphiæ. { { {Conopsariæ. { {Athericera {Œstrides. { { {Cryptogastræ. { { {Creophilæ. { { {Carpomyzæ. { {Muscides {Dolichoceræ. { {Gonocephalæ. { {Scathophilæ. { {Apteræ. { II. {Pupiparæ {Coriaceæ. {Phthiromyiæ[1432].
If you examine the Orders as here given, you will find that they mostly represent natural primary groups of his Classes, though with regard to their distribution you may perhaps feel disposed to differ from him. You will also think that his secondary and minor groups[1433], with the exception of some of his sections, merit the same character. Indeed, he has left far behind all his predecessors in the progress that he has made towards extricating the true system. Setting out from a common centre he holds on his unwearied course, endeavouring to trace every set of objects that branches from it to its extreme term. But though he studied insects analytically with unrivalled success, he was not always equally happy in his synthetical arrangement of them. I do not here so much speak of the result which must necessarily follow from any arrangement in a series, and which cannot well be avoided; but I allude particularly to his intire adoption of the Geoffroyan system in the Coleoptera, which has prevented him in many instances from seeing the natural distribution of his groups.
In 1798, two years after the publication of Latreille's first enunciation of his system, M. Clairville, a very acute and learned Swiss Entomologist, drew up the following analytical table of insects.
SECTIONS.
{ 1. Elytroptera { (Coleoptera). { 2. Deratoptera { Mandibulata { (Orthoptera). { { 3. Dictyoptera { { (Neuroptera). { Pterophora { { 4. Phleboptera { { { (Hymenoptera). { { { { { 5. Halteriptera { { { (Diptera). Insecta { { Haustellata { 6. Lepidioptera { { (Lepidoptera). { { 7. Hemimeroptera { { (Hemiptera). { Aptera {Haustellata 8. Rophoteira. {Mandibulata 9. Pododunera.
Every one will think that the change of the received names of the Orders, here denominated Sections, is perfectly needless. The principal merit of this system is the division of insects, tacitly pointed out by Fabricius, into two groups or subclasses, from the mode in which they take their food.
Lamarck,--whose merits as a Zoologist, except in one point[1434], are of the highest order,--in his Système des Animaux sans Vertèbres, which was published in 1801, adopts the above division of insects; but, after Aristotle[1435], he makes the Hymenoptera an intermediate Order between the masticators and those that take their food by suction; he places the Lepidoptera at the head of the latter, and the Aphaniptera, which he denominates Aptera, at the end[1436]: the Hexapod, Octopod, and Polypod Aptera he considers as Arachnida[1437]. In his last great work (Histoire Naturelle des Animaux sans Vertèbres) he includes the Hymenoptera amongst the masticators, and reverses the disposition of his Orders, beginning with his Aptera and ending with the Coleoptera[1438].
M. Le Baron Cuvier, in his Anatomie Comparée (1805) divided Insecta into two subclasses, from the presence or absence of maxillæ: thus--
With Maxillæ. Without Maxillæ.
1. Gnathaptera. 1. Hemiptera.
2. Neuroptera. 2. Lepidoptera.
3. Hymenoptera. 3. Diptera.
4. Coleoptera. 4. Aptera.
5. Orthoptera.
His Gnathaptera include the Isopod Crustacea, the Arachnida, the Polypod, and some of the Octopod and Hexapod Aptera; and his Aptera--Pulex, Pediculus, and the Acarina, with the exclusion of Hydrachna[1439]. It is remarkable enough that his Class as it stands, with a slight alteration, returns into itself, thus forming a circle; for his first Order (Gnathaptera) contains Hydrachna and the Thysanura, and his last (Aptera) ends with the Anoplura, and Acarina.
All the French Entomologists have followed Olivier and Latreille in adopting, with some variation, Geoffroy's system with regard to the Coleoptera, which has rendered them all more or less artificial. Dumeril has constructed a table of the Order, arranged differently from that above given[1440] of Latreille; but not more natural, for the very same reason.
Our learned countryman, Dr. Leach, by his zoological labours has thrown much light on the natural distribution of the Animal Kingdom, and no department of that kingdom is more indebted to him than the Annulosa; of which I have before stated to you his Classes[1441]. I shall now give a table of his Orders of Arachnida and Insecta Latr. and also his families, &c. of his Classes Myriapoda and Arachnides[1442].
CLASS. ORDER. FAMILY.
{ Glomerides. { Chilognatha { Iulides. { { Polydesmides. Myriapoda { { { Cermatides. { Syngnatha { Scolopendrides. { Geophilides.
{ Podosomata { Pycnogonides. { { Nymphonides. { { { Sironides. { Polymerosomata { Scorpionides. { { Tarantulides. { { { Solpugides. Arachnides { Dimerosomata { Phalangides. { { Araneïdes. { { { Trombidides. { { Gammasides. { Monomerosomata { Acarides. { Cheyletides. { Eylaïdes. { Hydrachnides.
{Ametabolia { Thysanura. { { Anoplura. { { { Coleoptera. { { Dermaptera. Insecta { { Orthoptera. { { Dictyoptera. { { Hemiptera. { { Omoptera. {Metabolia { Aptera. { Lepidoptera. { Trichoptera. { Neuroptera. { Hymenoptera. { Rhiphiptera. { Diptera. { Omaloptera.
I have before expressed my sentiments upon several of these Orders[1443]: I shall not here repeat them, but shall merely observe, with respect to those I have not adopted, that, though perhaps not entitled to rank as Orders, most of them form natural groups. His Orders, however, of Arachnida must be excepted from this remark, since they are evidently artificial. His analyses of his Orders, though in general they give natural groups, are usually not carried so far as those of M. Latreille, so as seldom to indicate what may properly be denominated families. He has made his nomenclature for his so-called families more uniform and satisfactory than that of the French Entomologist: and we may say, with respect to the extent and effect of his zoological labours,--Nihil non tetigit, et omnia quæ tetigit ornavit.
7. Era of MacLeay, or of the Quinary System. I have more than once stated to you in my former letters the bases upon which the system which I am in the last place to explain to you is built. You know the Sub-kingdoms and Classes into which its learned and ingenious author, upon a novel and most remarkable plan, has divided the Animal Kingdom[1444]. I shall now copy for you his diagram of the Annulosa.
I have before sufficiently noticed these Classes, or Orders as Mr. MacLeay terms them, of the Sub-kingdom Annulosa: I shall here therefore only throw out a few remarks on their composition. With regard to their circular distribution in the Crustacea, Mr. MacLeay thinks the series runs from the Branchiopods or Monoculus L. to the Decapods or Cancer L.; and so on, till by means perhaps of the genus Bopyrus, which Fabricius regards as a Monoculus, it returns to the Branchiopods again. This circle, through Porcellio, a kind of wood-louse, &c., which has only a pair of antennæ and at first but six legs, is connected with the Ametabola Class, which beginning with Glomeris goes by the other Chilognatha (Iulus L.), having also six legs at first, and certain Vermes to the Anoplura, and terminates in the Chilopoda (Scolopendra L.) their cognate tribe[1445]. From the Ametabola Mr. MacLeay proceeds to the Mandibulata, between which two groups he has discovered no osculant one, but he takes the Anoplura of the former as the transit to the Coleoptera in the latter; from whence passing to the Orthoptera, &c., he finally returns by the Hymenoptera. Between the Mandibulata likewise and Haustellata he finds no osculant class: but as the affinity between the Trichoptera and Lepidoptera is evident, proceeding by the Homoptera he returns to the Lepidoptera by certain Diptera, as Psychoda, &c. From the Aptera Lam. or Pulex L. he passes by the osculant class Nycteribida to the Arachnida; and beginning with the Acaridea, he goes to the Scorpionidea, and so to the Aranidea or spiders, which he connects with the Decapod Crustacea;--thus forming his great circle of five smaller ones, each of which, as well as that which they form, returns into itself[1446].
We next take his Circles of Mandibulata: thus--
In this arrangement of the tribes, as he calls them, of Mandibulata, Mr. MacLeay sets out from the Coleoptera, which he distributes, according to the supposed typical forms of their larvæ, into five minor groups, sufficiently noticed on a former occasion[1447]. From this tribe or Order he proposes to pass by Atractocerus to the osculant Order Strepsiptera, and from thence by Myrmecodes and the Ants to the Hymenoptera. From hence he next proceeds to his Trichoptera; in which, as we have seen[1447], he places not only Phryganea L., but also Tenthredo L. and Perla Geoffr., making his transit by Sirex L.; forming an osculant Order which he denominates Bomboptera. From this his way to the Neuroptera is by the Perlides, with Sialis as an osculant Order under the name of Megaloptera: he enters by Chauliodes, and leaves it by Panorpa or Raphidia by means of Boreus, forming also an osculant Order (Raphioptera) for the Orthoptera; which he enters by Phasma, Mantis, &c., and leaves by Gryllus, entering the Coleoptera again by the osculant Order Dermaptera formed of Forficula L.: and thus returning to the point from which he set out[1448]. He has not, however, made this return of the series into itself so clear in each order, excepting in the Orthoptera, as he has done in the whole Class or Sub-class. Thus in the Coleoptera there appears no particular affinity between the Predaceous and Vesicant beetles, his first and fifth forms[1449], or his Chilopodimorphous Coleoptera, and his Thysanurimorphous.
To enter fully into his doctrine of Analogies would lead us into a very wide field, and occupy a larger space than I can afford; I must therefore refer you to his work for more particular and detailed information on that subject. With regard to the analogy between opposite points of contiguous circles, you may get a very good idea of it from his diagram of Saprophagous and Thalerophagous Petalocerous beetles, which I here subjoin.
It is a very singular circumstance that in these two circles we have two sets of insects,--one impure in its habits and feeding upon putrescent food, and the other clean and nourished by food that has suffered no decay,--set in contrast with each other, and that in each of the opposite groups, the one has its counterpart in some respect in the other. In none is this more striking than the Scarabæidæ and Cetoniadæ, both remarkable for having soft membranous mandibles unfit for mastication, and both living upon juices, the one in a putrescent and the other in an undecayed state[1450].
Our learned author in subsequent works has stated every circle to be resolvable into two superior groups, which he denominates normal or typical, and three inferior ones, which he calls aberrant or annectent[1451].
Before I conclude this account of the various general systems that have distinguished the different entomological eras, i must say a few words on those partial ones which have been founded on the neuration of the wings of insects. Frisch, who died in 1743, attempted something in this way[1452]: Harris, in his Exposition of English Insects published in 1782, had arranged his Hymenoptera and Diptera according to characters derived from this same circumstance[1453]: Mr. Jones in the Linnean Transactions had made good use of it in dividing the Diurnal Lepidoptera into groups[1454]: and in the Monographia Apum Angliæ, the characters exhibited by the various groups into which Linné's genus Apis was resolvable, as to the neuration of their wings, were described[1455]. But M. Jurine was the first Entomologist who made that circumstance the keystone of a system; which indeed he restricted to Hymenopterous and Dipterous insects, but which might be extended much further. As this system has been before sufficiently enlarged upon[1456], I need here only mention it.
* * * * *
To particularize the various entomological works in every department of the science, that have appeared since the commencement of the era of Fabricius, would require a volume. Such was its progress and spread, that in every corner of Europe the pens and pencils of able and eminent men, whose works have almost all been quoted in the course of our correspondence, have been employed to illustrate it[1457].
I may observe, however, that the Internal Anatomy of Insects, a branch of Entomology which on account of its difficulty, from the extreme nicety required in dissecting them, had before been cultivated by scarcely more than a single student in an age, has now attracted numerous votaries. In Germany--Carus, Gaede, Herold, Posselt, Ramdohr, Rifferschweils, Sprengel, and others, have distinguished themselves in this arena: and in France, besides the illustrious Baron Cuvier (himself a host), Marcel de Serres, Leon Dufour, and very recently, by his elaborate essays On the Flight of Insects and its wonderful apparatus, one of the most acute of anatomical physiologists, M. Chabrier,--have all contributed greatly to the elucidation of this interesting part of the science. In our own country very little has hitherto been effected in this line; but a learned Oxford Professor (Kidd) has presented to the Royal Society an account of the anatomy of the Mole-cricket, which entitles him to an eminent station amongst the above worthies.
I may likewise further observe, that the pictorial department of Entomology was, during the period I am speaking of, carried to its greatest perfection. Painters of insects formerly were satisfied with giving a representation generally correct, without attempting a faithful delineation of all the minor parts, particularly as to number;--for instance, the joints of the antennæ and tarsi, the areolets of the wings, &c.: but now no one gives satisfaction as an entomological artist unless he is accurate in these respects.
I am, &c.
FOOTNOTES:
[1316] See above, p. 364--.
[1317] Genes., ii. 19--.
[1318] Pol. Synops. on Genes. ii.
[1319] Genes. i. 25.
[1320] Linn. Trans. iv. 51--. See Levit. xi. 20--.
[1321] The Neuroptera appears to be the only Order not so signalized. It is worthy of notice that insects are usually noticed generically and not specifically in Scripture. On the insects of Scripture see Bochart Hierozoic. ii. 1. iv.
[1322] Isai. vii. 18. Joel ii. Rev. ix. 3.
[1323] Prov. xxx. 24--.
[1324] 1 Kings iv. 33.
[1325] Linn. Trans. i. 5.
[1326] VOL. III. p. 6.
[1327] Ibid. l. i. c. 5.
[1328] Ibid. l. iv. c. 7.
[1329] Ibid.
[1330] Ibid. l. v. c. 19.
[1331] Aristotle calls winged insects Pterota when he would distinguish them from those that are apterous, and Ptilota when he contrasts them with birds. (Comp. Hist. Anim. l. iv. c. 1. with l. i. c. 5.) Sometimes he calls birds thus contrasted Schizoptera, and insects Holoptera. De Anim. Incess. c. 10.
[1332] Ibid. l. i. c. 5.
[1333] Ibid. and l. iv. c. 7.
[1334] Ibid.
[1335] Hist. Anim. l. iv. c. 1.
[1336] Ibid.
[1337] Ibid. l. viii. c. 11.
[1338] Gr. Ον τροφης χαριν εχει οδοντας αλλ' αλκης. Αλκη means Strength of mind, Fortitude, Strenuousness, also Help:--it here probably signifies their strenuous use of their oral organs in fulfilling their instincts. De Partib. Anim. l. iv. c. 5.
[1339] Hist. Anim. l. iv. c. 7.
[1340] Ibid.
[1341] Gr. Αερσιποτητος αραχνη. Dies. lin. 13.
[1342] Hist. Nat. l. xi. c. 25.
[1343] VOL. I. p. 481. VOL. II. p. 121--.
[1344] De Natur. Animal. l. vi. c. 20.
[1345] Ibid. l. xv. c. 1.
[1346] Opera vi. 683.
[1347] Ibid. 153--.
[1348] Ibid. 154, 233, 265, &c.
[1349] Opera vi. 676, 679, 680.
[1350] See above, p. 428.
[1351] Opera vi. 682--.
[1352] Esperienz. ed Osserv. i. 42--.
[1353] Pultency's Sketches of Botany in England, i. 86.
[1354] Theatr. Insect. Epist. Ded. i.
[1355] Theatr. Insect. Epist. Ded. i.
[1356] Theriotroph. Siles. 455.
[1357] Aristotle (Hist. Anim. l. i. c. 1.) says, "The sponge seems to have some sensation: as a proof, it is not easily plucked up, unless, so they say, the attempt is concealed."
[1358] Lister's Goedart, Præf. ii.
[1359] See VOL. I. p. 65--, where these terms are explained.
[1360] Swamm. Bibl. Nat. i. 38--.
[1361] Ibid. 92--.
[1362] Ibid. 119--.
[1363] Ibid. ii. 1--.
[1364] Ibid. 31--.
[1365] Ibid. 30.
[1366] Hist. Ins. Prolegom. ix.--
[1367] These are all Annelida.
[1368] Larvæ.
[1369] Various Aptera and the Bed Bug.
[1370] Nymphon.
[1371] Scorpio.
[1372] Spiders, Phalangia, and Mites.
[1373] Iulus.
[1374] Scolopendra.
[1375] Annelida.
[1376] This section is divided by the author into thirteen tribes.
[1377] Lepidoptera.
[1378] Apis, Bombus, &c.
[1379] Vespidæ.
[1380] Andrena, Halictus, Nomada, &c.
[1381] Crabro, Philanthus, Cerceris, &c.
[1382] Serifera? Ichneumon, &c.
[1383] Trichoptera.
[1384] Pimpla Manifestator, and other Ichneumonidæ, with a long ovipositor.
[1385] Our author has followed Swammerdam in this unnatural separation of those Diptera whose metamorphosis is coarctate from the rest; and in associating with them the Chalcidites, whose metamorphosis is really different. Into this error both were led by system.
[1386] Philos. Lett. &c. 141.
[1387] Ibid. 343.
[1388] Ray died in 1705, and Linné was born in 1707.
[1389] When a boy he attempted to introduce wasps and bees into his father's garden, to the great annoyance of the old gentleman.--Stœver's Life of Linnæus, 4.
[1390] Ibid. 75.
[1391] Linn. Philos. Botan. n. 87, 188, 189.
[1392] See above, p. 342, n. 5.
[1393] Linn. n. 291.
[1394] Fn. Suec. Præf.
[1395] VOL. III. p. 681--.
[1396] Histoire abrégée des Insectes.
[1397] See the opposite page.
[1398] The first volume of his Mémoires was published in 1752.
[1399] The first volume of this work was published in 1734, the sixth and last in 1742.
[1400] Reaum. i. Mém. vi. vii. and Mém. ii. 68--.
[1401] Smith's Tour, iii. 150.
[1402] VOL. I. p. 175. Also see above, p. 166--.
[1403] Bonnet i. 19--.
[1404] We have been informed that these valuable remains are at length likely to be rescued from oblivion, and given to the public.
[1405] VOL. II. p. 48, note^a.
[1406] Since the former edition of these volumes was published, another and most important association has been formed, having for its object the Animal Kingdom solely; which not only has a museum to receive specimens of dead animals (by the liberal donation of its present learned secretary, of his own rich collection, and from other sources, already most interesting both as a spectacle and to the student), but also a Vivarium, in which a considerable and curious assemblage of living animals may be seen. This association, which is named THE ZOOLOGICAL SOCIETY, is principally indebted for its formation to the efforts of a great, amiable, and lamented character, the late Sir Thomas Stamford Raffles, whose merits were equally conspicuous both as a Politician and a Naturalist, and who was its first President.
[1407] Linné is recorded to have said, "Si Dominus Fabricius venit cum aliquo Insecto, et Dominus Zoega cum aliquo Musco, tunc ego pileum detraho et dico: Estote doctores mei." Stœver's Life of Linnæus. 186.
[1408] Fab. Philos. Entomolog. Præf.
[1409] VOL. III. p. 416.
[1410] Philos. Entomolog. vi. §. 2. Syst. Ent. Prolegom.
[1411] From Ελευθερος, Free.
[1412] Derivation uncertain. Perhaps Αυλων, A long and narrow space or tract.
[1413] Συνιστημι, To stand together.
[1414] Πιεζω, To press.
[1415] Οδους, A tooth.
[1416] Μιτος, A thread.
[1417] Unogata is probably a mistake for Onychata; from Ονυξ, A claw.
[1418] Doubtless for Polygnatha; from Πολυς, Many, and Γναθος, A jaw.
[1419] Κλειστος, Closed, and Γναθος.
[1420] Εξω, Without, and Γναθος.
[1421] Γλώσσα, A tongue.
[1422] Ῥυγχος, A rostrum.
[1423] Αντλια, A pump.
[1424] Dispositio insectorum sistit divisiones s. conjunctiones eorum, et est artificialis quæ Classes et Ordines, et naturalis quæ genera, species, et varietates docet. Philos. Entomol. vi. §. 2.
[1425] Ibid. §. 7.
[1426] Latreille Gen. Crust. et Ins. iii. 214.
[1427] With respect to Natural Genera he says--"Cavendum tamen ne nimis imitando naturam systematis amittamus filum Ariadneum." Ibid. § 6.
[1428] Fab. Entomolog. Syst. em. et auct. i. Præf. iv.
[1429] Fabricius calls this a chaos, and threatens to prove it, but he never fulfilled his threat. See Fab. Supplem. Præf. i.
[1430] Introd. ad Hist. Nat. 401.
[1431] See N. Dict. d'Hist. Nat. x. article Entomologie; and Familles Naturelles du Règne Animal 262--.
[1432] These tables, except the first, are taken from the Familles Naturelles du Règne Animal. As a new edition of M. Le Baron Cuvier's Règne Animal is preparing, M. Latreille will doubtless give in it a still more improved arrangement of the Crustacea, Arachnida, and Insecta.
[1433] Several of the minor groups given in the table he has further resolved before he arrives at his genera.
[1434] VOL. III. p. 348, note^c.
[1435] See above, p. 433.
[1436] Syst. des Anim. sans Vertèbr. 185.
[1437] Ibid. 171.
[1438] Anim. sans Vertèbr. iii. 332--.
[1439] Anat. Comp. i. t. viii.
[1440] Expos. d'une Meth. Nat. 17.
[1441] VOL. III. p. 19.
[1442] Linn. Trans. xi. 376. N. B. I have transferred from the Arachnida his suborder Notostomata, as he subsequently placed it at the end of Insecta, under the Omaloptera.
[1443] See above, pp. 378, 380, 385, 390.
[1444] VOL. III. p. 14.
[1445] See VOL. III. p. 25--. and above, p. 394--.
[1446] Hor. Entomolog. c. vi.
[1447] See above, p. 382.
[1448] Hor. Entomolog. 420--.
[1449] Ibid. 422.
[1450] Other systems or methods have been promulgated by various authors, as by Schæffer, Scopoli, Geoffroy, &c. Walckenaer and Blainville have proposed one founded on the number of the legs of insects; but those in the text are the principal and best known.--N. Dict. d'Hist. Nat. xvi. 277.
[1451] Linn. Trans. xiv. 59--. Annulos. Javan. 6. See above, p. 408.
[1452] Latreille Gen. Crust. et Ins. iii. 226. note 1.
[1453] Præf. ii.
[1454] Linn. Trans. ii. 63--.
[1455] Mon. Ap. Angl. i. 211--.
[1456] VOL. III. p. 620. n. 3.
[1457] It may not be unprofitable here to mention those works which the Entomologist may find it most useful to consult in various departments of the science. For descriptions of the Genera and Species of insects in general, he must have recourse to the Entomologia Systematica emendata et aucta of Fabricius, and its Supplement; to the volumes he subsequently published under the titles Systema Eleutheratorum, Rhyngotorum, Glossatorum, Piezatorum, and Antliatorum; to the Genera Crustaceorum et Insectorum of Latreille; to the same department of the Règne Animal of Cuvier; and to the Animaux sans Vertèbres of Lamarck. He will find the genera of Linné and Fabricius illustrated by figures, in Rœmer's Genera; and many of the species described by the latter in Coquebert's Illustratio Iconographica. In our countryman Drury's beautiful Illustrations of Natural History, a large number of new and rare insects are depicted; and in Mr. Donovan's Insects of China, India, and New Holland, some of the most brilliant and interesting that have been imported from those countries. Panzer's Faunæ Insectorum Germanicæ Initia has little short of 3000 figures of insects of every Order (a considerable number of which are found to inhabit Britain), by the celebrated Sturm; and the latter, in his Deutschlands Fauna, has illustrated many Coleopterous genera analytically (as has also M. Clairville the weevils and Predaceous beetles of Switzerland in his Entomologie Helvétique) by his admirable pencil. Beetles in general are well figured and described in Olivier's splendid Entomologie; as are those of Europe in a beautiful work now in course of publication, under the title of Coleoptères d'Europe, by MM. Latreille and Dejean. The latter author has also begun a work on this Order under the title of Species général des Coléoptères de la Collection de M. Le Comte Dejean; two volumes of which have appeared, containing part of the Carabici Latr. but I fear it has stopped for want of encouragement. Had the descriptions been less verbose it would have had a better chance of success. For the Orthoptera and Hemiptera, the student must have recourse to Stoll's Spectres, Mantes, Sauterelles, Grillons, Blattes, Cigales, and Punaises. To a knowledge of the species of Lepidoptera, the admirable figures of Cramer (Papillons Exotiques de trois Parties du Monde), Esper (Schmetterlinge, Tagschmetterlinge), Hübner (Schmetterlinge, &c.), and Ochsenheimer's valuable Schmetterlinge von Europa, with the continuation by Treitschke, will afford a useful avenue. Meigen also, author of a most valuable work on the Europæan Diptera, is publishing at this time a work on Lepidoptera under the title of Europäische Schmetterlinge. To the Hymenoptera Jurine and Christian are the best guides, and to the Diptera Meigen.
With regard to works in British Entomology in general--Donovan's Natural History of British Insects, and Samouelle's Entomologist's Useful Compendium, will be found very excellent helps to the student. For the British Genera, the most important work that has yet appeared is Mr. John Curtis's British Entomology, in which not only are the insects admirably represented, but their trophi correctly delineated, accompanied by able descriptions. For the Coleoptera of our country, Mr. Marsham's Entomologia Britannica should be consulted: for the Lepidoptera, the Butterflies of Lewin, Mr. Haworth's useful Lepidoptera Britannica, and Miss Jermyn's Butterfly-Collector's Vade Mecum; and for the English species of Linné's genus Apis, the Monographia Apum Angliæ. A British Fauna Insectorum, under the title of Illustrations of British Entomology, has at length been happily begun by a gentleman (J. F. Stephens, Esq.) who both by his accurate knowledge of the subject, and the extent of his collection of British Insects, is best qualified to undertake it. As far as it has proceeded, it is ably executed, and possesses this advantage, (an advantage seldom to be obtained in works published periodically,) that it finishes, as far as possible, as it goes.
Letter XLIX
_GEOGRAPHICAL DISTRIBUTION OF INSECTS; THEIR STATIONS AND HAUNTS; SEASONS; TIMES OF ACTION AND REPOSE._
Though no subject is more worthy of the attention of the Entomologist than the Geographical Distribution of insects, yet perhaps there is none connected with the science, for the elucidation of which he is furnished with fewer materials. The geographer of these animals sitting by his fireside, even supposing his museum as amply stored as that of Mr. MacLeay, and the habitats of its contents as accurately indicated, still labours under difficulties that are almost insuperable; so that it is next to impossible, with our present knowledge of the subject, to give satisfactory information upon every point which it includes. Had he the talents and opportunities of a Humboldt, and could, like him, traverse a large portion of the globe, he would endeavour to note the elevation, the soil and aspect, the latitude and longitude, the mean temperature and meteorological phænomena, the season of the year, the kind of country, and other localities connected with the insects he captured, and so might build his superstructure upon a sure basis. But these are things seldom registered by travellers that take the trouble to collect insects; who, if they specify generally the country in which any individual was found, think they have done enough. But to say that an insect was taken in India, China, New Holland, and North or South America,--when we consider the vast extent of those regions,--is saying little of what one wishes to know even with respect to its habitat. You must regard therefore, after all, what I have been able to collect,--and for which I am greatly indebted to the labours of my few but able precursors in this walk,--as merely approximations to an outline, rather than as a correct map of insect Geography.
Amongst the numerous obligations that he conferred upon Natural History, Linné was the first Naturalist who turned his attention to the Geographical Distribution of its objects, especially that of the Vegetable Kingdom[1458]: and the accomplished traveller Baron Humboldt, by the observations he made on this subject in the course of his peregrinations in tropical America, has furnished the Botanist with a clue which, duly followed, will enable him to perfect that part of his science; an end to which the learned observations of Messrs. R. Brown and Decandolle have greatly contributed[1459]. With regard to animals, Mr. White, so long ago as 1773, had observed that they, as well as plants, might with propriety be arranged geographically[1460]: and in 1778 Fabricius in his Philosophia Entomologica applied the principle to insects[1461]. Nearly forty years elapsed before any improvement or enlargement of this last department was attempted; when in 1815 M. Latreille, stimulated by what had been effected in Botany, in a learned and admirable memoir[1462] endeavoured to place Entomology in this respect by the side of her more fortunate sister: and subsequently Mr. W. S. MacLeay, in the memorable work so often quoted in our correspondence, has viewed the subject in another light, and added some important information to what had been before collected[1463].
The point now under consideration naturally divides itself into two principal branches;--the numerical distribution of insects, and the topographical.
I. By the numerical distribution of insects I mean not only the number which PROVIDENCE has employed to carry on its great plan on this terraqueous globe, or any given portion of it; or of the species of which each group or genus may be supposed to consist; or of the comparative number of individuals furnished by each species,--points of no easy solution: but more particularly their distribution according to their functions, whether they prey upon animal or vegetable matter, and in its living or decaying state.
We have no data enabling us to ascertain with any degree of accuracy the actual number of species of insects and Arachnida distributed over the surface of the globe; but it is doubtless regulated in a great degree by that of plants. We should first then endeavour to gain some just though general notion on that head. Now Decandolle conjectures that the number of the species of plants, 60,000 being already known, may be somewhere between 110,000 and 120,000[1464]. If we consider with reference to this calculation, that though the great body of the mosses, lichens, and sea-weeds are exempt from the attack of insects, yet as a vast number of phanerogamous plants and fungi are inhabited by several species, we may form some idea how immense must be the number of existing insects; and how beggarly does Ray's conjecture of 20,000 species[1465], which in his time was reckoned a magnificent idea, appear in comparison! Perhaps we may obtain some approximation by comparing the number of the species of insects already discovered in Britain with that of its phanerogamous plants. The latter,--and it is not to be expected that any large number of species have escaped the researches of our numerous Botanists,--may be stated in round numbers at 1500, while the British insects, (and thousands it is probable remain still undiscovered,) amount to 10,000; which is more than six insects to one plant. Now though this proportion, it is probable, does not hold universally; yet if it be considered how much more prolific in species tropical regions are than our chilly climate, it may perhaps be regarded as not very wide of a fair medium. If then we reckon the phanerogamous vegetables of the globe in round numbers at 100,000 species, the number of insects would amount to 600,000. If we say 400,000, we shall perhaps not be very wide of the truth. When we reflect how much greater attention has been paid to the collection of plants than to that of insects, and that 100,000 species of the latter may be supposed already to have a place in our cabinets[1466], we may very reasonably infer that at least three fourths of the existing species remain undiscovered.
Certain groups and genera are found to contain many more species than others: for instance, the Coleoptera and Lepidoptera Orders than the Orthoptera and Neuroptera; the Rhincophora than the Xylophagi: the Dytiscidæ than the Gyrinidæ; Aphodius than Geotrupes; Carabus than Calosoma. Again, some insects are much more prolific than others. Thus the Diptera Order, though not half so numerous with respect to species as the Coleoptera, exceeds it greatly in the number of individuals, filling the air in every place and almost at every season with its dancing myriads. We rarely meet with a single individual of the most common species of Calosoma or Buprestis; whilst the formicary, the termitary, the vespiary, and the bee-hive send forth their thousands and tens of thousands; and whole countries are covered and devastated by the Aphides and the Locusts. An all-wise PROVIDENCE has proportioned the numbers of each group and species to the work assigned to them. And this is the view in which the numerical distribution of insects is most interesting and important: and we are indebted to Mr. W. S. MacLeay for calling the attention of Entomologists more particularly to this part of our present subject.
With regard to their functions, insects may be primarily divided into those that feed upon animal matter and those that feed upon vegetable. At first you would be inclined to suppose that the latter must greatly exceed the former in number: but when you reflect that not only a very large proportion of Vertebrate animals, and even some Mollusca[1467], have more than one species that preys upon them, but that probably the majority of insects, particularly the almost innumerable species of Lepidoptera, are infested by parasites of their own class, sometimes having a different one appropriated to them in each of their preparatory states[1468], and moreover that a large number of beetles and other insects devour both living and dead animals,--you will begin to suspect that these two tribes may be more near a counterpoise than at first seemed probable. In fact, out of a list of more than 8000 British insects and Arachnida taken several years ago, and furnished chiefly by Mr. Stephens, I found that 3894 might be called carnivorous, and 3724 phytiphagous[1469]; so that, speaking roundly, they might be denominated equiponderant.
Carnivorous and phytiphagous insects may be further subdivided according to the state in which they take their food,--whether they attack it while living, or not till after it is dead. To adopt Mr. W. S. MacLeay's phraseology, the former may be denominated thalerophagous, and the latter saprophagous. The British saprophagous carnivorous insects, compared with those that are thalerophagous, are about as 1:6; while the phytiphagous ones are as 1:9. The thalerophaga in both tribes may be further subdivided as they take their food by suction or mastication: in the carnivorous ones, the suckers to the masticators in Britain are nearly as 1:6; but with respect to the phytiphagous tribe you must take into consideration that some insects imbibing their food by suction in their perfect state (as the great body of the Lepidoptera), masticate it when they are larvæ: deducting therefore from both sides the insects thus circumstanced, the masticators will form about three fourths of the remaining British thalerophagous insects. Another circumstance belonging to this head must not be passed without notice:--there are certain insects feeding upon liquid food that do not suck, but lap it. This is the case with the Hymenoptera, who, though they are mandibulate, generally lap their food (the nectar of flowers) with their tongue, and may be called lambent insects: nor is this practice confined to that order, but all the mandibulate insects that feed on that substance merit the same appellation. The absorption of this nectar is so important a point in the economy of nature, that a very large proportion of the insect population of the globe in their perfect state, are devoted to it. Considerably more than half the species indigenous to Britain fulfill this function, and probably in tropical countries the proportion may be still larger.
To push this analysis still further--Amongst our carnivorous thalerophaga, aphidivorous insects are about as 1:14; and amongst the phytiphagous, the fungivorous ones form about a twentieth; and the granivorous about a twenty-fifth part of the whole. Again: in the saprophaga the lignivorous tribes form more than half, and the coprophagous ones more than a third.
If you wish to know further the relative proportions of the different Orders to each other--The Coleoptera may be stated as forming at least 1:2 of our intire insect population; the Orthoptera and Dermaptera as about 1:160; the Hemiptera as 1:15; the Lepidoptera as more than 1:4; the Neuroptera with the Trichoptera as 1:29; the Hymenoptera as about 1:4; the Diptera as not 1:7; and the Aptera and Arachnida as perhaps amounting to 1:19[1470].
To extend this inquiry to exotic and more particularly to extra-European insects, in the present state of our knowledge, would lead to no very satisfactory results. The lists we have are so imperfect, that those which tell most in this country,--I mean the more minute insects and the Brachyptera--have hitherto formed a very small, if any part, of the collections made out of Europe. Mr. W. S. MacLeay however, who, besides his father's (particularly rich in Petalocera), has had an opportunity of examining the Parisian and other cabinets, finds that the species of coprophagous insects within the tropics, to those without, are nearly in the proportion of 4:3; and that the coprophagous Petalocera, to the remainder of the saprophagous ones, may be represented by 3:2[1471]. It may be inferred, from the superabundance of plants and animals in equinoctial countries, that the number of species of insects in general is greater within than without the tropics: the additional momentum produced by the vast size of many of the tropical species must also be taken into consideration.
II. There are three principal points that call for attention under the second branch of our present subject--the topographical distribution of insects; namely, their Climates, their Range, and their Representation.
i. Entomologists, taking heat for the principal regulator of the station of insects, have divided the globe into entomological climates. Fabricius considers it as divisible into eight such climates, which he denominates the Indian, Egyptian, Southern, Mediterranean, Northern, Oriental, Occidental, and Alpine. The first containing the tropics; the second, the northern region immediately adjacent; the third, the southern; the fourth, the countries bordering on the Mediterranean sea, including also Armenia and Media; the fifth, the northern part of Europe interjacent between Lapland and Paris; the sixth, the northern parts of Asia where the cold in winter is intense; the seventh, North America, Japan, and China; and the eighth, all those mountains whose summits are covered with eternal snow[1472]. M. Latreille objects to this division, as too vague and arbitrary and not sufficiently correct as to temperature; and observes, with great truth, that as places where the temperature is the same, have different animals, it is impossible, in the actual state of our knowledge, to fix these distinctions of climates upon a solid basis. The different elevations of the soil above the level of the sea, its mineralogical composition, the varying quantity of its waters, the modifications which the mountains, by their extent, their height, and their direction, produce upon its temperature; the forests, larger or smaller, with which it may be covered; the effects of neighbouring climates upon it,--are all elements that render calculations on this subject very complicated, and throw a great degree of uncertainty over them[1473]. This learned Entomologist would judiciously consider entomological climates under another view,--that which the genera of Arachnida and insects exclusively appropriated to determinate spots or regions would supply[1474]. Linné's dictum with regard to genera will here also apply; "Let the insects point out the climate, and not the climate the insects." If you expect invariably to find the same insects within the same parallels of latitude, you will be sadly disappointed; for, as our author further observes, "The totality or a very large number of Arachnida and insects, the temperature and soil of whose country are the same, but widely separated, is in general, even if the countries are in the same parallel, composed of different species[1475]." The natural limits of a country,--as mountainous ranges, rivers, vast deserts, &c.,--often also say to its insect population, "No further shall ye come;" interposing a barrier that it never passes[1476]. Humboldt observes, with respect to the Simulia and Culices of South America, that their geographical distribution does not appear to depend solely on the heat of the climate, the excess of humidity, or the thickness of forests; but on local circumstances that are difficult to characterize[1477]: and Mr. W. S. MacLeay makes a similar observation upon that of Gymnopleurus[1478]. So that the real insect climates, or those in which certain groups or species appear, may be regarded as fixed by the will of the CREATOR, rather than as certainly regulated by any isothermal lines. Still, however, under certain limitations, it must be admitted that the temperature has much to do with the station of insects. The increase of caloric is always attended with a proportional increase in the number and kind of the groups and species of these beings. If we begin within the polar regions of ice and snow, the list is very meager. As we descend towards the line, their numbers keep gradually increasing, till they absolutely swarm within the tropics. Something like this takes place in miniature upon mountains. Tournefort long since observed at the summit of Mount Ararat the plants of Lapland; a little lower, those of Sweden; next, as he descended, those of Germany, France, and Italy; and at the foot of the mountain, such as were natural to the soil of Armenia. And the same has been observed of insects. Those that inhabit the plains of northern regions have been found on the mountains of more southern ones; as the beautiful and common Swedish butterfly Parnassius Apollo, on the mountains of France, and Prionus depsarius on those of Switzerland[1479].
M. Latreille, having given a rapid survey of the peculiar insect-productions of different countries, next attempts a division of the globe into climates, which he thinks may be made to agree with the present state of our knowledge, and be even applicable to future discoveries. He proposes dividing it primarily into Arctic and Antarctic climates, according as they are situated above or below the equinoctial line; and taking twelve degrees of latitude for each climate, he subdivides the whole into twelve climates. Beginning at 84° N. L. he has seven Arctic ones, which he names polar, subpolar, superior, intermediate, supratropical, tropical, and equatorial: but his antarctic climates, as no land has been discovered below 60° S. L., amount only to five, beginning with the equatorial and terminating with the superior. He proposes further to divide his climates into subclimates, by means of certain meridian lines; separating thus the old world from the new, and subdividing the former into two great portions,--an eastern, beginning with India, and a western, terminating with Persia. He proposes further that each climate should be considered as having 24° of longitude, as well as 12° of latitude[1480]. In this chart of insect Geography he states that he has endeavoured to make his climates agree with the actual distribution of insects[1481]; and it should seem that in many cases such an agreement actually does take place: yet the division of the globe into climates by equivalent parallels and meridians, wears the appearance of an artificial and arbitrary system, rather than of one according with nature.
He has also pointed out another index to insect climates, borrowed from the Flora of a country. Southern forms in Entomology, he observes, commence where the vine begins to prosper by the sole influence of the mean temperature; that they are dominant where the olive is cultivated; that species still more southern are compatriots of the orange and palmetto; and that some equatorial genera accompany the date, the sugar-cane, the indigo and banana[1482]. The idea is very ingenious, and, under certain limitations, supplies a useful and certain criterion. For though none of these plants are universal in isothermal parallels of latitude; yet, as plants are more conspicuous than insects, the Entomologist, furnished with an index of this kind, may by it be directed in his researches for them; and in all countries in which there is a material change of the climate, as in France, there will be a proportional change in the vegetable accompanied by one in the insect productions.
ii. In considering the range of insects I shall first advert to that of individual species. At the extreme limits of phanerogamous vegetation we find a species of humble-bee (Bombus arcticus), which, though it is not known to leave the Arctic circle, has a very extensive range to the westward of the meridian of Greenwich, having been traced from Greenland to Melville Island; while to the eastward of that meridian it has not been met with. In Lapland its place appears to be occupied by B. alpinus and lapponicus, with the former of which, though quite distinct, it was confounded by O. Fabricius; but whether these range further eastward of that meridian has not been ascertained. From its being found in the Lapland Alps[1483], it may be conjectured that B. alpinus ranges as high on this side as B. arcticus on the other, and may perhaps be found in Nova Zembla. Some species that have been taken in Arctic regions are not confined to them. Of this kind is Dytiscus marginalis, which appears common in Greenland, abundant in Britain, and is dispersed over all Europe; while D. latissimus is more confined, neither ranging so far to the north or south; and though found in Germany, not yet discovered in Britain. Other species have a still more extensive range, and are common to the old world and the new. Thus Dermestes murinus, Brachinus crepitans, Tetyra scarabæoides[1484], Pentatoma juniperina, Cercopis spumaria, Vanessa Antiopa, Polyommatus Argiolus, Hesperia Comma, Vespa vulgaris, Ophion luteus, Helophilus pendulus, Oscinis Germinationis, and many besides, though sometimes varying slightly[1485], inhabit both Britain and Canada: and though vast continents and oceans intervene between us, New Holland, and Japan; yet all have some insect productions in common. With the former we possess the painted-lady butterfly (Cinthia Cardui), with scarcely a varying streak: and Thunberg, in his list of Japan insects, has mentioned more than forty species that are found also in this country. Whether any species has a universal range may be doubted, unless indeed the flea and the louse may be excepted. On the other hand, some are confined within very narrow limits. Apion Ulicis for instance, abundant upon Ulex europæus in Britain, has not, I believe, been found upon that plant on the continent.
The geographical distribution of groups, is, however, far more interesting than that of individual species: for in considering this we see more evidently how certain functions are devolved upon certain forms, and can scan the great plan of PROVIDENCE, in the creation of insects, more satisfactorily than by confining our attention to the latter. Groups, according to their range, may be denominated either predominant, dominant, sub-dominant, or quiescent.
1. M. Latreille has observed, that where the empire of Flora ceases, there also terminates that of Zoology[1486]. Phytiphagous animals can only exist where there are plants; and those that are carnivorous and feed upon the former, must of necessity stop where they stop. Even the gnat, which extends its northern reign so high[1487], must cease at this limit; while, where vegetation is the richest and most abundant, there the animal productions, especially the insect, must be equally abundant. I call that, therefore, a predominant group, members of which are found in all the countries between these points, or from the limits of animal-depasturing vegetation in the polar regions to the line.
Generally speaking, the carnivorous insects, whether thalerophagous or saprophagous, are of this description. Calosoma, which devours Lepidopterous larvæ, though poor in species and individuals, is widely scattered. Captain Frankland found C. calidum in his Arctic journey; C. laterale and curvipes inhabit tropical America[1488]: C. Chinense, as its name indicates, is Chinese[1489]; Mr. MacLeay has an undescribed species from New Holland; and C. retusum was taken in Terra del Fuego. Another genus, equally universal and richer in numbers, is the lady-bird (Coccinella), which keeps within due limits the Aphides of every climate from pole to pole. The Libellulina pursue their prey both in Greenland and New Holland. The saprophagous carnivora are also similarly predominant;--the Silphidæ, the Dermestidæ, the Brachyptera, the Muscidæ, prey on carcases wherever the action of the solar beam causes them to become putrid. Many of the above insects have probably their capital station, or that where the species are most numerous, in or near the tropics; but the metropolis of the Brachyptera, at least as far as we can judge from our present catalogues, is within the temperate zone, particularly in Britain[1490]. The coprophagous Petalocera are most abundant in the hottest climates; but the Aphodiadæ form a predominant group: Professor Hooker took one species in Iceland[1491], and it probably ascends higher; others are found in India and China: but the metropolis of the group is within the temperate zone. Perhaps no genus is more completely universal than Bombus (Bremus Jur.), which, although its centre or metropolis is likewise in the northern temperate zone, extends from Melville Island to the line. It is remarkable that some of the tropical Bombi wear the external aspect of Xylocopæ, the kindred genus most prevalent in warm climates; and, vice versâ, some Xylocopæ resemble Bombi. I have a Brazilian undescribed species of the latter genus, whose black body and violet-coloured wings would almost cause it to be mistaken for a variety of X. violacea; and B. antiguensis and caffrus F., (though their aspect belies it,) which misled Fabricius, are true Xylocopæ. I shall mention only one other predominant group, but that one of no common celebrity, formed of the gnats, or genus Culex. These piping pests, with their quiver--"venenatis gravida sagittis"--annoy man almost from the pole to the line. What remarkably distinguishes them, (as was formerly observed[1492],) and also the Simulium or true mosquito,--they appear to prevail most in the coldest and the hottest climates, and the Laplander and the tropical American are equally their prey; while the inhabitants of the temperate zone, with some exceptions, suffer but little from them: so that they may be stated to have both an arctic and a tropical metropolis.
2. There are other groups which, though their empire extends to the tropics, fall short of the polar circles:--these I call dominant groups. Of this description are some of the Scarabæidæ. Onthophagus is found both in the old world and in the new, and in the temperate and torrid zones. Its principal seat appears to be within the tropics, but it may almost be said to have also a northern metropolis. More than one species have been taken in New Holland. In general, tropical insects exceed those of colder climates in size; but in the genus we are speaking of, the European species are usually larger than the Indian. Copris seems more abhorrent of cold than its near relation Onthophagus. C. lunaris, which ranges northward as far as Sweden, is the only recorded species found in Europe out of Spain. Latreille says, that all the large species of this genus are equinoctial: but C. Tmolus, described and figured by Fischer[1493], found in Asia near Orenburg, north of 50° N. L., is as big as C. Gigas or bucephalus. Another dominant group of Petalocera, remarkable for the bulk and arms of its tropical species, are the mighty Dynastidæ, the giants and princes of the insect race. Though their metropolis is strictly tropical, yet the scouts of their host have wandered even as far as the south of Sweden, where one of them, Oryctes nasicornis, is extremely common. O. Grypus[1494] and some other species are found in South Europe; but though in a torpid state they can endure unhurt the severity of a Scandinavian winter, they cannot when revived stand the cold that often pinches Britons in the midst of summer, and therefore are unknown in our islands[1495]. The Sphæridiadæ, whose metropolis is within the northern temperate zone, extend from thence beyond the line, since Dr. Horsfield found two species in Java[1496]. It is probable, indeed, that this group is predominant. Some dominant groups begin at a lower latitude. Of this description are the carpenter-bees (Xylocopa), whose larvæ are preyed upon by that of the Horiadæ[1497] under two forms, which extend from the tropics to about 50° N. L. Others are not common to both worlds. Thus, while Cantharis is the gift of PROVIDENCE to America as well as the old world, Mylabris is confined to the latter, where its range is very extensive;--in Europe, from South Russia to Italy and Spain; in Asia, from Siberia to India; and in Africa, from the shores of the Mediterranean to the Cape of Good Hope; which last continent, to judge from our present lists, especially the vicinity of the Cape, may be called the metropolis of the group[1498]. On the other hand, the Rutelidæ and Chlamys, which have a range from Canada to the tropics, (within which is their metropolis,) are purely American groups. Many more might be named under this head, but these will suffice for examples.
3. I call those subdominant groups, which either never enter the tropics, or those tropical ones whose range does not exceed 50° of N. L. in the old world, or 43° in the new. I make this difference because, as M. Latreille observes, the southern insects which in Europe begin between 48° and 49° N. L., in America do not reach 43°.[1499] But though the winters in Canada, within the same parallel as France, are longer and more severe than those even of Great Britain or of Germany, yet the summers are intensely hot; so that though tropical species do not range so high, those of a tropical structure, as Mr. W. S. MacLeay has intimated[1500], may be found at a higher latitude in the new world than in Europe.
The genus Melöe affords an instance of a subdominant group of the first description. It ranges from Sweden to Spain and the shores of the Mediterranean, and seems a tribe almost confined to Europe, where it is not very unequally distributed. Of registered species Britain possesses the largest proportion; but Mr. W. S. MacLeay is of opinion that Spain is its true metropolis[1501]. I have a species of this genus, taken in North America by Professor Peck. The splendid genus Carabus ranges still further north than Melöe[1502]. A very fine species (C. cribellatus) inhabits the polar regions of Siberia[1503]; but the metropolis of the group appears to be the temperate zone: some, however, have been found in northern Africa; and Sir Joseph Banks captured one in Terra del Fuego. Of those whose range is between the tropics and 50° N. L. we may begin with Cicada. One species, indeed, has been found by Mr. Bydder and others, a little higher, near the New Forest, Hampshire. We may take Scolia for an example of a subdominant group beginning more southward. Its species first appear about 43° N. L., and abound in warm climates. In general most of those insects which M. Latreille denominates meridional,--such as Scarabæus, Onitis, Brentus, Scarites, Mantis, Fulgora, Termes, Scorpio, &c.--come under the present head, and in fact all tropical forms that wander to any distance within the above limits from their metropolis.
4. By quiescent groups I mean those that have none, or no high range as to latitude, from their centre or metropolis. I say as to latitude, because these groups have often an extensive one as to longitude. Thus, Mr. W. S. MacLeay has remarked to me, that Goliathus appears to belt the globe, but not under one form. The types of the genus are the vast African Goliaths (G. giganteus, &c.), which, as well as G. Polyphemus, and another brought from Java by Dr. Horsfield, have, like Cetonia[1504], the scapulars interposed between the posterior angles of the prothorax and the shoulders of the elytra[1505]: while the South American species (G. micans, &c.) have not this projection of the scapulars; in this resembling Trichius. Mr. MacLeay further observes, that the female of the Javanese Goliathus is exactly a Cetonia, while that of the Brazilian is a Trichius. But quiescent groups have not generally this ample longitudinal range. Thus, Euglossa, in both its types,--one represented by Eu. cordata, and the other by Eu. surinamensis,--is confined to the tropical regions of America. Doryphora, likewise American, seems equally confined. Asida, though a southern genus, is not found to enter the tropics; and Manticora and Pneumora are in nearly the same predicament.
Under the present head we may consider what may perhaps be denominated without much impropriety endemial groups; by which I mean those groups that are regulated, as to their limits, not so much by the temperature, or the northing and southing of the latitude, as by the general aspect and circumstances of the country. Thus, the vast and nearly insular continent of Africa, almost as wide as it is long, and situated in or near the tropics, instead of inland seas or sea-like rivers, is intersected by parched sandy deserts, extending far and wide; circumstances which, though in the vicinity of its streams it is humid, impart an unusual degree of aridity as well as heat to its general atmosphere; so that it well merits the poet's epithet, Leonum arida nutrix; and is also peculiarly fitted for all such animals, especially insects, as delight in a dry, sandy, hot country, particularly such as are predaceous in their habits. America, on the other hand, exhibits quite an opposite character. It is long, and comparatively narrow; surrounded, and almost divided into two continents, by immense circumfluent oceans; watered every where by rivers and lakes that emulate seas: in some parts covered by interminable forests; in others, intersected by ridges of the loftiest mountains. These circumstances, except in its Llanos, Pampas, or table-land, give a general character of humidity to its atmosphere, and fit it particularly for the production of a vast variety of peculiar plants, and for the residence of numerous and peculiar phytiphagous insects and other animals[1506]. Midway between these two continents lies a third (for so the vast island of New Holland may be denominated), which presents new features in its general aspect, and consequently new forms both in its Flora and Fauna, mixed with many old ones parallel to those both of the new world and the old. Perhaps Europe and Asia, with several that are peculiar, agree more in their animal productions than the continents just described.
Let us next particularize a few of the peculiar types that distinguish particular continents and countries. The genera Manticora, Graphipterus, Glaphyrus, Eurychora, Pneumora, Masaris, and many others, are peculiar to Africa. In Asia alone we find Mimela[1507], Euchlora[1508], Colliuris, Catascopus[1509], Apogonia[1510], a peculiar type of Horia, &c. In America, Agra, Galerita, Nilio, another type of Horia, Tetraonyx, Rutela, Doryphora, Alurnus, Erotylus, Scotinus[1511], Cupes, Corydalis, Labidus, Heliconius, Castnia, &c. And in New Holland, Helluo, Elephastomus, Anoplognathus, Diphucephala[1512], Cerapterus, Heleus, Adelium, Notoclea, Achilus, Thynnus, Nycterobius, &c.
The countries bordering upon the Mediterranean, the Black, and the Caspian seas, agree in producing similar insects. These countries, and the Cape of Good Hope though so distant from them, appear to be the principal seat of Heteromerous Coleoptera, of the genera Lixus and Brachycerus, and of the conical Buprestes[1513]. But the insects of Guiana, on one side the Cordilleras, differ from those of New Granada and Peru on the other; and similar differences are observed in other neighbouring countries separated by natural boundaries.
iii. Another head connected with the topographical distribution of insects relates to their representation of each other. Here we may observe, that some insects represent each other only in their form; others also in their function; and others in both. I shall give some instances of each. In Brazil there is a group of petalocerous beetles (Chasmodia), one of the Rutelidæ, which in New Holland has a representative, as to form, in one of the Cetoniadæ (Schizorhina[1514]), which, having soft mandibles, must have a different function:--it is to be observed, however, that these insects appear to approach each other in the series of affinities. Again, the Carabidæ may in the same country be said to have a representative in the remarkable heteromerous genus Adelium[1515], which is altogether an analogy. Others are representative only in their function. The general function of insects is to remove nuisances and to check redundances,--the saprophagous tribes do the one, and the thalerophagous the other. In going from the poles to the line,--in proportion as the heat increases, the quantum of work of both kinds increases; and new forms are either added to the old ones, so as to increase their momentum; or new ones, more powerfully talented, replace the old ones, and act in their stead: thus we see a gradual and interesting change take place in proportion as we approach the maximum of heat and of insect population. At the Cape, the universal Cicindelæ are aided by Manticora; in North America, the Silphidæ by a new group, the type of which is Silpha Americana (Necrophila, K.MS.); in South America, Copris by Phanæus. Again: Colliuris and Drypta of the old world, in the new give place to Ctenostoma and Agra. The honey and wax of Europe, Asia, and Africa, is prepared by bees congenerous with our common hive-bee (Apis); while in America this genus is not found as a native, but is replaced by Melipona and Trigona[1516]; and in New Holland by a still different but undescribed type. The Melolonthidæ and Rutelidæ of the old and new world appear to have their work done in that country by the brilliant and numerous Anoplognathidæ. The Rhipicera of Brazil is of a different type from that of New Holland. The singular genus Cremastocheilus of North America has its representative in Africa in Genuchus[1517]. The Lucani of the rest of the world give place in New Holland to Lamprima and Ryssonotus.--I could produce a much greater number of examples, but these are sufficient to explain my meaning.
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Having thus given you some, though an imperfect account, of the geographical distribution of insects, I am next to say something concerning their local distribution in any district, or their favourite haunts; a knowledge of which, with respect to those of our own country, is indispensable to the collector.
The surface of a country consists either of mountains, hills and valleys, or of plains. It is diversified by forest, wood, or copse; and watered by rivers, rivulets, lakes, and pools. Those parts that are not clothed with wood are either open or inclosed, forming grassy downs, heaths, pastures, meadows, morasses, and arable land. The soil also is equally various:--we find clay, loam, marl, chalk, vegetable mould, moor, sand, &c. The mountains and hills are either covered with a stratum of soil, or are rocky and bare; the arable lands are divided by living or dead fences, the latter formed of various materials,--or else they are open, and the property only marked out by grassy balks, &c. All these places abound in shrubs and plants; some local, and some generally distributed. But besides the land and its fresh waters, we must look also to the sea, and its sandy, pebbly, or rocky shores, and the sea-wrack that is cast up upon them; the estuaries that receive its tides; the brackish waters and saline marshes in its vicinity. All the above places, when opportunity serves, the Entomologist should explore, for in almost all he will find peculiar kinds of insects.
As mountains and hills have usually their own Flora, the insects appropriated to alpine plants can only be met with where the pabulum is found. Here also those northern insects that are impatient of a warmer climate will take their station, if they migrate to the southward[1518]. The predaceous beetles likewise sometimes frequent a mountainous district. Carabus glabratus was first taken by Professor Hooker on Ingleborough; and probably, if the Welsh and Scotch mountains were duly investigated by an Entomologist, many novelties would reward his toils. The valleys and plains, especially those of a sunny exposition, abound in insects. When the heat of the atmosphere indisposes you for motion, you will find it no unprofitable or unpleasant employment, lying on the grass, to search for minute beetles, which you will there find coursing about amongst the tufts and roots of the herbage. Thus you may procure many of the Pselaphidæ, which you would not otherwise meet with. Even when the grass is grown up, insects are fond of alighting upon its spikes, and thence drop or run to the ground. Should circumstances ever carry you abroad to the steppes or grassy plains of Tartary, or to Hungary, you would find there two or three species of the singular genus Lethrus, which burrows in the soil. Every hole is inhabited by a male and female;--from it they issue to attack the plants or vines; and having cut out the heart of a plant, go backwards like a crab with the prize to their burrow. At the time of pairing, sometimes violent battles, encouraged by the female, take place between the male and a stranger of that sex desirous of admission, which cease only with the death or flight of the stranger[1519]. The vicinity and borders of woods generally abound in insects of every Order; and if you proceed, as hereafter directed, will furnish you with numerous prizes, especially of Lepidoptera. Here alone you can meet with the purple emperor butterfly (Apatura Iris); and if properly equipped you may readily secure him.
The waters you will find nearly as prolific in insects as the land. In them, amongst the beetles, you may expect to meet with Dytiscus, Haliplus, Pælobius, Hyphydrus, Hydroporus, Noterus, Colymbetes, and other Dytiscidæ; the Gyrini, Hydrophili, Hydrænæ, Elophori, &c.: under stones, the Elmis; and in the mud, the Parni and Heteroceri. Some Sphæridiadæ are also aquatic: I have taken more than once Cercyon hæmorrhoidale from the under side of a piece of wood immersed in a canal[1520]. Even a few of the weevil tribes are to be met with in water. Lixus paraplecticus, Tanysphyrus Lemnæ, Bagous atrirostris, are of this description. A species of Ceutorhynchus of Germar's third family (C. Natator K.) swims well. On aquatic plants you must look for Helodes and the splendid Donaciæ, which, living on submerged shoots and roots of these plants in their larva state, continue to attend them when perfect. Amongst the _Eutrech_in_a_[1521],--Elaphrus, Notiophilus, and Bembidium frequent humid places, as the banks of rivers and ponds; and in such a station, under the roots of Potentilla anserina, Polygonum, &c. if you should be fortunate enough to find Omophron limbatum, which connects the _Eutrech_in_a_ with the _Eunech_in_a_, you will make a valuable addition to the list of British insects. In the waters also you will meet with many Heteropterous Hemiptera; as Gerris, Hydrometra, and Velia, and all the Hydrocorisæ or water-bugs. On aquatic plants the larvæ of some Lepidoptera feed, as Hydrocampa stratiotata, potamogata, &c. Those also of the Trichoptera must be sought for in the water: and if you should feel inclined to see an interesting collection of their very curious cases, Mr. Sheppard of Wrabness can gratify your curiosity. Though few or no Hymenoptera frequent this element, vast numbers of Diptera are there alone to be met with in their preparatory state, particularly the gnats. We learn from Humboldt a curious fact with respect to those of South America, or the Zancudos; that, with some exceptions, these pests do not frequent those rivers called by the natives black waters, but only those which they name white waters[1522]. Of the Aptera, the genera Hydrachna, Eylaïs and Limnochares are purely aquatic. Several spiders will walk over the water; and one species (Argyroneta aquatica) inhabits it[1523]. The stagnant waters in your vicinity will produce different species from running ones. Thus Haliplus elevatus, &c. inhabits only the latter, while the majority of the Dytiscidæ abound most in the former: the more minute ones may be sought for with success amongst the duckweed that covers a pool. I do not recollect finding any insect in waters absolutely salt[1524]; but brackish waters produce peculiar species: in these only, Hydræna marina occurs; and many of those large-eyed Cimicidæ (Acanthia), as A. saltatoria, littoralis, and Zosteræ occur in places where salt water has been. Latreille observes, that the genus Pimelia is to be met with only where the soil is impregnated with saline particles, or where the species of the genus Salsola abound[1525].
Heaths, though they do not afford numerous insects, have their rarities. Cicindela sylvatica, Carabus nitens and arvensis, frequent them, and are not elsewhere to be seen. Curculio nebulosus is also to be found on them, in places where the turf has been peeled; and some scarce Lepidoptera. In their vicinity, in sunny sandy banks, some of the rarer Ammophilæ and Pompili may be taken; and it is here only that I have ever met with Panurgus[1526]. Meadows and pastures are not to be neglected. Early in the year, when they are yellow with the blossoms of Ranunculus bulbosus, Leontodon Taraxacum, &c., many minute beetles, and not a few Hymenoptera and Diptera, frequent them. Morasses also have their peculiar insects. In these you will meet with some of the scarcer _Eutrech_in_a_; as Chlænia holosericea and nigricornis, Blethisa multipunctata, various Bembidia, &c. In this kind of district in the Isle of Ely Aphodius plagiatus has been taken, and that scarce and beautiful butterfly Lycæna Virgaureæ. Where land is cultivated the Entomologist as well as the farmer may expect a harvest. Insects in general are fond of perching on the summit of a blade of grass or corn; and many minute ones may be taken coursing about in the ears of the latter: some to devour the fungilli that infest the grain, as Phalacrus corruscus in Reticularia Segetum; others to attack the grain itself, as Cecidomyia Tritici; others to destroy these destroyers, as three little parasites belonging to the Chalcidites[1527]. But I have already mentioned most of those insects that are to be expected in such situations[1528]: I shall therefore only further observe, that upon barley particularly you will meet with the species of Latreille's genus Cephus.
With respect to soils, those that are light appear to be most prolific in insects. Warm sandy banks are frequented by Cicindela campestris, Opatrum sabulosum, Helops quisquilius, &c.: in them (when of a southern aspect) Ammophilæ, Pompili, and numerous Hymenoptera nidificate. Chalk also attracts various insects. Latreille observes, that the Licini, Papilio Cleopatra, several species of Dasytes, and some Lamiæ, delight in this kind of soil[1529]:--in my own neighbourhood I have observed Polyommatus Corydon principally in chalk-pits. One of these pits, under a wood in an adjoining parish, has produced me several valuable insects. Here I took Apion ebeninum, Orobitis globosus, a new species of Evæsthetus, several of the rarer Pselaphidæ and Cholevæ, and Chætophorus cretifer before noticed[1530]. I do not mean, however, that all these are properly chalk insects; but they fall into these pits, where they are readily discerned, from the contrast of their colours with the whiteness of the chalk. By watching attentively the bottom of one, vast numbers in a warm day may be taken when they fall or are climbing upwards. Of all soils clay offers the fewest inducements to the Entomologist, who will lose both his time and labour in a clay-pit; while in one of sand, chalk, or marl, they will usually not be mispent. Vegetable earth also affords a harbour to various larvæ, and the pupæ of many nightfliers amongst the Lepidoptera, by digging in it, especially under trees, may be obtained. Even the bare rocks have their insect frequenters that take shelter in their fissures; and in the early part of your career especially you should always turn over large stones, as beneath them many of the Harpalidæ and other _Eutrech_in_a_ frequently lie hid: and in this situation, both in Suffolk and Sussex, Lomechusa emarginata, one of our scarcest Brachyptera, has been taken. Old trees also, and planks that have laid long without being moved, often afford a shelter to many of the minute Coleoptera; as Pselaphidæ, Aleocharidæ, Cryptophagidæ, Scymnidæ, &c. Live fences, especially when the hawthorn is in blossom, and where trees are also intermixed, are attended by innumerable insects of almost every description; and even the black-thorn will present you with one of our most splendid weevils (Rhynchites Bacchus). Dead fences are almost as fertile in insects as living ones. In gates, posts, rails, and other timber when felled, the timber-devouring tribes take their station:--between the bark and the wood are the Bostrichidæ; in the wood itself, the Anobidæ and the Capricorn beetles. Here also you may meet with many Hymenoptera, which either devour timber or nidificate in it,--as the Siricidæ, Chelostoma, Trypoxylon, Sapyga, and several Diptera. In the decaying hedgestakes and sticks, where the Sphæria decorticans has turned off the bark, you may meet with Anthribus brevirostris; with A. latirostris, and other beetles, in S. fraxinea; and A. albinus, which I have more than once captured as it was emerging from the fissure of a gate-post, probably feeds on some internal fungus. The grassy balks that separate open fields usually abound in umbelliferous plants, which are attended by numerous Hymenoptera and Diptera, particularly by the various species of the splendid tribe of Chrysidæ: and the grassy banks of fences, where the aspect is sunny, are generally bored by a variety of insects of the former Order, to prepare a nest for their young. Andrenidæ and Nomadidæ particularly select this situation, the latter probably depositing their eggs in the burrows of the former[1531]. By watching these places in the spring, you may perhaps have the good fortune to meet with a Stylops. It is singular, that some insects choose, for their own residence or that of their young, the hardest and most trodden pathways. Thus, some ants will build their subterranean apartments under gravel walks; and so do many species of the genus Halictus[1532], the habits and economy of which have been so ably detailed by M. Walckenaër[1533]: Cerceris also, and other Hymenoptera, will choose such places, however public, for the site of their nests or burrows. The ground is so consolidated by the constant foot, that they, probably find such situations spare them a world of labour, and therefore in their choice balance one inconvenience by another.
Though the sea itself, I believe, produces no true insects, yet there are many that constantly or occasionally haunt its shores. On the sand-hills of the Norfolk coast I found Ægialia globosa and Cicindela hybrida. Ceutorhynchus horridus inhabits thistles that grow near the sea. Under the Zostera and Fuci, (cast up both on its beach and the shores of estuaries,) many peculiar species of Cercyon, several Aphodii, and numerous Brachyptera, may often be found. In this situation the rare and singular Bledius armatus has been taken. At certain seasons of the year the beach and environs of the sea are covered by many species of Coccinella, which seem to bend their course thither from the inland country, as if they were about to emigrate[1534]. When the weather is fine and the tide begins to retire, at the line of its highest rise I have taken on the eastern coast a variety of insects, and amongst the rest Anomala Frischii. The inundations of rivers, except in the depth of winter, always bring a number of these little creatures, which float on the surface on bits of stick, weeds, &c.; and where they deposit these articles when the water begins to subside, you may generally reap a plentiful harvest of various kinds.
You see, now, how varied is the scenery to which the diversion of the Entomologist introduces him; that he is never out of his way: whether on hill or in valley; on upland or plain; on the heath or in the forest; on the land or on the water; in the heart of a country or on its shores;--still his game is within his reach. But in order to enable him to pursue it with greater prospect of success, he must recollect that not only is every face of the country to be explored, but both the plants and the animals that it produces; and that he must not turn with disgust from even the carcase or the excrement of the latter. As numerous species of herbivorous insects feed only on one kind of plant, the Entomologist, when he discovers a scarce one, should examine it with the hope of finding upon it a scarce insect. Sometimes it happens that only a single opportunity occurs in a man's life of seeing certain plants growing wild: such opportunities should never be neglected. Some insects also inhabit a plant in one district or season, and not in another. Thus the most beautiful of the Apions, A. Limonii[1535], though the plant it feeds upon usually abounds near the sea, I have discovered only on the northern coast of Norfolk; and another scarcely less beautiful, but more minute (A. Astragali[1536]), though I have sought for it year after year, Astragalus glyciphyllus being abundant near me, I never found but once. The blossoms of plants as well as the leaves must be inspected. In those of the rose, the Cetonia aurata is often taken[1537]; and in the bells of the different species of Campanula various bees may be captured enjoying a luxurious repose[1538]. No vegetable productions abound more in insect inhabitants than the Fungi. In Agarics several Diptera are to be taken, many Aleocharæ, Oxypori, &c.; in Boleti, the various species of Mycetophagus; in the arboreous ones, and under bark, more than one kind of Ips; and in Auricularia, as well as Boletus, the whole genus Cis. Upon living Vertebrate animals you must look for Pulices, Pediculi, Nirmi, Acari, and many Diptera, as Œstrus, Tabanus, Stomoxys, and the Pupipara of Latreille; and on the garden-snails for that curious genus Drilus, and some Acari[1539]. The caterpillars and pupæ of Lepidoptera, &c. will, as you have heard, furnish you with numerous ichneumons[1540]. On dead animals you will find the various species of Silphidæ, Nitidulidæ, Dermestidæ, Byrrhidæ, Chlolevidæ, Staphilinidæ, Muscidæ, &c.; and in excrement, various Scarabæidæ, Histeridæ, Aphodiadæ, Sphæridiadæ, the Brachyptera in general, and several Diptera[1541]. In putrescent roots and fruits, as the turnip, the cucumber, &c., you may also occasionally meet with rare Coleoptera.
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I must next say something upon the seasons of insects, and their times of appearance. Those that collect honey and pollen are generally among the first that proclaim the approach of spring; and their appearance may be dated from the blossoming of certain trees and plants of common occurrence. Other plants, accompanied by peculiar insects, blossom later; and so on till we arrive at the autumn. The earliest insect-season commences with the flowering of the sallow (Salix Caprea) usually accompanied in the garden by that of the crocus and the gooseberry. Then is your time to collect many species of wild bees and Diptera not afterwards to be met with: and various other insects now begin to emerge from their winter-quarters, or are produced from the pupa. Another and later season is marked by the general blossoming of the butter-cup (Ranunculus bulbosus), accompanied by the marsh-marygold (Caltha palustris) and ladies'-smock (Cardamine pratensis); when you may hunt the pastures, meadows, and marshes with success, and take some insects that do not show themselves later. The coprophagous insects are now abundant. Amongst others, Aphodius testudinarius, a perfectly vernal species, is now only to be taken, and usually flying. A third insect-season indicated by Flora, and a very prolific one, commences with the blossoming of the hawthorn, when you must desert the meads for the inclosures. At this time all nature begins to put on her gayest attire, and all her insect tribes are now on the alert, and fill the air. They are almost universally attracted by the sweet and lovely blossoms of the plant just named: so that by examining them you may entrap some of every Order, and many that during the year will appear no more. Even many of the saprophagous insects will sip nectar from these flowers. The umbelliferous plants proclaim the fourth season of insects, particularly the wild carrot and parsnip. You will scarcely ever fail to find, if the weather is genial, Hymenopterous and Dipterous insects of various genera,--especially such as have a short tongue,--engaged in collecting the honey from those plants. Here you may take some of the rarer Chrysidæ, Crabronidæ, Cercerides, &c., and occasionally even Coleoptera. The last insect-season may be dated from the general flowering of the thistle tribe. When these are in blossom is the best time of all to collect the humble-bees (Bombus[1542]), the leaf-cutter bees (Megachile[1543]), and many other Apiariæ, which alone by their long tongues can imbibe the honey and collect the pollen of these flowers. The male humble-bees frequent them to the last, and often seem as if they were intoxicated with their sweets.
But perhaps you may prefer considering the whole summer appearance of insects as divided into three principal seasons. This may thus be done. Their vernal season may commence Florente Caprea, and end Florente Oxyacantha; their summer, Florente Oxyacantha and Florentibus Umbellatis; their autumn, Florentibus Umbellatis and Florente Carduo. In the first, the number of insects will be daily increasing; in the second (which is the harvest of the Entomologist, when his eyes and his hands ought to be every where), they will reach their utmost complement; and in the third, they will be gradually decreasing in number, till they generally die, or go into winter-quarters. At this time many minute Diptera and Ichneumons take shelter from the weather in the windows of our apartments. These seasons will not always exactly correspond with our usual reckoning, and take place at the same time; since, being regulated by our varying temperature, they will be sometimes sooner and sometimes later, sometimes longer and sometimes shorter. Though I have not named a brumal season, because insects are in winter usually torpid,--yet some, as Diurnea Novembris, Cheimatobia brumata, and many Tipulariæ, even then make their appearance.
If you ask, Whether it be not possible to regulate our Entomological seasons by the appearance of insects themselves? I should answer, that probably this might be done; but that further observations seem wanted to enable us to do it satisfactorily. Perhaps the appearance of Formica rufa beginning the business of the year might form the commencement of one season; the flight of the orange-tip butterfly (Pontia Cardamines[1544]), of a second; a third might be indicated by the swarming of Melolontha vulgaris; a fourth, by that of Amphimalla solstitialis; and the last, by the appearance in numbers of Aphodius ciliaris, which in the autumn fills every horse-dropping.
Some insects are so ephemeral, that they are to be found in numbers only for a few days, and then disappear for that season. Of this description are the Ephemeræ, much of whose history has been detailed to you. Those of which De Geer has given an account (E. vulgata) appeared about the end of May or the beginning of June, and continued about a fortnight[1545]; while those which Swammerdam observed did not come forth till the middle of June, and lasted only three days[1546]. The same period distinguished those of which Reaumur has compiled so interesting a history, but they did not show themselves before the middle of August[1547]. My kind friend Mr. Marsham not long before his death copied for me some memoranda he had made with respect to the sudden appearance of Cercopis bifasciata. On one occasion the white dress of a lady sitting upon a haycock was covered by these insects; but on the following day the same steps were taken at the same time to procure some, when after the most diligent search not a single one could be found. The same circumstance was observed a few years afterwards by another friend of his. He himself was of opinion that the insects in question were then migrating[1548].
I may here observe, that the London amateurs have particular seasons for collecting moths. For the imago they go into the woods in April, May, June, and October. For the larvæ they take the beginning of April, June, the beginning of July, and September. They dig for pupæ late in July, and in January and February.
* * * * *
I shall lastly make a few observations upon the times of action and repose of insects, the knowledge of which, as far as it can be obtained, is of essential use to the industrious collector. Entomologists have divided the Lepidoptera, with a view to this circumstance, into diurnal, crepuscular, and nocturnal; or butterflies (Papilio L.), hawkmoths (Sphinx L.), and moths (Phalæna L.). These terms may be applied to insects in general.
i. Diurnal insects are abundant. Butterflies in particular fly generally at no other time: they accompany the sun in his course, and before he sets disappear. Some other Lepidoptera, though not so named, are day insects:--such are the Zygænidæ, &c. amongst the hawkmoths; and amongst the moths, Plusia Gamma, the Phytometræ solares of Haworth[1549], and some others. Numberless Coleoptera belong to this section. The Donaciæ fly only when the sun is out and the air is warm; they are then extremely agile and difficult to take. Some Hopliæ swarm in the day before noon, and then disappear[1550]: most of the tetramerous beetles also appear to be diurnal. The Libellulina and many other Neuroptera may also be so termed; and the Hymenoptera almost universally, with the sole exception of the Formicidæ[1551]. Amongst the Diptera, if we leave out the Tipulariæ, the rest will be found for the most part to belong to the present section.
ii. Crepuscular insects, strictly speaking, are those that appear only during the twilight, whether in the morning or evening; but the term may be understood, with some latitude, to signify all those insects that are seen only in the morning and evening, though after sunrise and before sunset. Of these, some come forth only in the morning, others only in the evening, and others both morning and evening. My memory only furnishes me with a single instance of an insect whose principal appearance and flight are in the morning. Catocala nupta I have often seen flying at this time, about six or seven o'clock, and never at any other: I am not however prepared to assert that it does not appear in the evening or night, but I have then never met with it. In the evening more particularly you hear the hum of the dung-beetle (Geotrupes), which Linné thought the prognostic of a following fine day; and of the swarms of Melolontha vulgaris and Amphimalla solstitialis. Then also many other Coleoptera are in the air; especially before a thunderstorm, a state of the atmosphere that particularly excites insects[1552]: Ptinus imperialis and germanus I have never taken except under these circumstances. Then the Ephemeræ sport in the air, and lead their mystic dance. The majority of the hawkmoths are then too on the wing, with their long tongues imbibing the nectar of the flowers while they hover over them, both morning and evening.
iii. In the night the main body of the moths take their flight, as well as a vast number of Coleoptera and insects of other orders. At this time the Blattæ and crickets leave their hiding-places and run about: but the other Grylli L., though they sing in the night, fly only in the day. Then also the Carabi, like beasts of prey, leave their dark retreats,--in this differing from the Cicindelæ, which are diurnal,--and prowl about to entrap other unwary insects. Then, likewise, the female glowworm hangs out her lamp of love, and the male, led by it, wings his way to her: and then the water-beetles (Dytisci, Gyrini, &c.) forsake the waves and become tenants of the air.
Could we with certainty discover the stations in which insects after their excursions take their repose, we might capture many that we now search for in vain. Several of these stations were pointed out in a former part of this letter where I detailed their usual haunts. I may here add, that numbers of them, when reposing, conceal themselves from their enemies on the under side of the leaves of trees and plants. Moths, especially the Noctuidæ, may often be met with in woods, as before observed[1553], on the north side of the trunks of trees. Mr. Marsham related to me, that once a little before sunset, observing over his head a number of insects on the wing moving on in one direction, he caught some of them, and they proved to be Labia minor. Struck with the circumstance, he watched them several evenings; and on one, as he was looking about a melon-pit for insects, he saw these little animals alight on the frame, hastily fold up their wings, and entering under the glasses, run down its sides and bury themselves in the loose earth. This he observed repeatedly. The onward flight of these insects was therefore evidently their return from their diurnal cruise to their nocturnal station.--This happened in September.
I am, &c.
FOOTNOTES:
[1458] Linn. Philos. Botan. § 334.
[1459] Linn. Trans. x. 20--. &c. Dict. des Scienc. Nat. xviii.
[1460] Selborne i. 173.
[1461] Philos. Entomolog. ix. § 20.
[1462] Mém. du Mus. 1815.
[1463] Hor. Entomolog. 42--. 518.
[1464] Essai Elément. de Géograph. Botan. 62.
[1465] Wisdom of God, &c. 2d edit. 9.
[1466] Hor. Entomolog. 469. This calculation includes the Crustacea.
[1467] It has lately been discovered that the larva of Drilus flavescens, a beetle, feeds upon the common snail. (Bulletin des Scienc. Nat. 1824. iii. 297; v. 110; vi. 221.) I have found an Acarus on the same animal.
[1468] See above, p. 219--.
[1469] We employ this term, because the more common one, herbivorous, does not properly include devourers of timber, fungi, &c.
[1470] If we consider the number of species of Acari, Nirmi, Poduræ, and Araneidæ, this proportion will appear moderate.
[1471] Hor. Entomolog. 48.
[1472] Philos. Entomolog. ix. § 20.
[1473] Géograph. Génér. des Ins. 5.
[1474] Ibid.
[1475] Ibid. 7--.
[1476] Ibid. 8, 11.
[1477] Personal Narrat. E. T. v. 88. He says also that each stream almost has its peculiar species (Ibid. 98), and that they sometimes emigrate to stations they had not infested before. Ibid. 106--.
[1478] Hor. Entomolog. 519.
[1479] Latr. ubi supr. 3.
[1480] Géographie, &c. 22--.
[1481] Ibid. 27.
[1482] Géographie, &c. 20--.
[1483] See above, p. 494.
[1484] As this insect is the type of a distinct genus amongst the Scutelleridæ, I have distinguished it by the name Fabricius gave the whole tribe.
[1485] M. Latreille (Géographie, &c. 8.) seems to regard these varieties as distinct; in which case they would be the representatives of the species named in the text: but the variations are mostly so slight, as not to afford any satisfactory distinctive characters.
[1486] Géogr. Génér. des Ins. 2.
[1487] When I described the Melville Island insects for Captain Sabine, I received from him no Culices; but I afterwards saw in his possession a genuine one from thence.--K.
[1488] Linn. Trans. xii. 380--. n. 6, 7.
[1489] Ibid. n. 5.
[1490] Dejean in his catalogue gives only 434 species; while Mr. Stephens, four years ago, had 550, and has since increased the number to above 600.
[1491] Journal of a Tour in Iceland, 272.
[1492] VOL. I. p. 115--.
[1493] Entomogr. Russ. Coleopt. t. xiii. f. 1.
[1494] Ahren's Fn. Europ. i. 1.
[1495] Hor. Ent. 47--.
[1496] Annulosa Javanica, 36.
[1497] See the Rev. L. Guilding's admirable History of Xylocopa Teredo and Horia (Cissites Latr.) maculata, Linn. Trans, xiv. 313--.
[1498] Out of 51 species described by Bilberg, 28 are African, and 19 of these are from the Cape.
[1499] Géogr. Génér. des Ins. 18.
[1500] Hor. Entomolog. 45.
[1501] Dr. Leach has described 8 British species (Linn. Trans. xi. 37.); Dejean has 7 Spanish ones.
[1502] I have a very splendid species of this genus taken by C. C. Elwes Esq. on the Pyrenees, which is undescribed, and falls under none of the count Dejean's Families, having its elytra perfectly smooth, without striæ, punctures, &c. It is of a brilliant golden green. It stands in my cabinet under the name of C. lævigatus. K.
[1503] Fischer Entomogr. Russ. 90--. t. viii. f. 13.
[1504] VOL. III. p. 562.
[1505] Major General Hardwicke gave me one of this description from Nepal.
[1506] Latr. Géograph. &c. 18--.
[1507] Linn. Trans. xiv. t. iii. f. 4.
[1508] Hor. Entom. 147.
[1509] Linn. Trans. ubi supr. f. 1.
[1510] Ibid. xii. t. xxi. f. 9.
[1511] Ibid. f. 14.
[1512] To this genus belong Melolontha aurulenta. Ibid. 400; and M. sericea. Ibid. 463.
[1513] Latr. Géograph. 7.
[1514] Cetonia atropunctata and Brownii of Linn. Trans. (xii. 464. t. xxiii. f. 6.) belong to this genus.
[1515] Linn. Trans. xii. t. xxii. f. 2; t. xxiii. f. 7.
[1516] Latreille, Géograph. &c. 10.
[1517] Linn. Trans. xiv. 569.
[1518] See above, p. 496.
[1519] Fischer, Entomogr. Russ. i. 135.
[1520] From finding it in water, Fabricius considered this insect as a Hydrophilus, but it is a true Cercyon.
[1521] See above, p. 401.
[1522] Personal Narrat. E. T. v. 91--.
[1523] See VOL. I. p. 470--.
[1524] A species of Gyrinus (G. Viola aquatica), described by Modeer (Linn. Syst. Nat. Ed. Gmel. i. 1612. n. 9.), is said to inhabit salt water.
[1525] Géograph. &c. 6.
[1526] Apis *., a. Mon. Ap. Angl. ii. 178--.
[1527] Linn. Trans. iv. 30--. v. 96--. t. iv.
[1528] VOL. I. LETTER VI.
[1529] Géograph. &c. 6.
[1530] VOL. II. p. 255.
[1531] These, as well as Melecta, are probably a kind of Cuckow-bee. Mon. Ap. Angl. i. 150.
[1532] Melitta * *. b. Mon. Ap. Angl. i. 138--.
[1533] Mémoires sur le gènre Halicte.
[1534] VOL. II. p. 9.
[1535] Linn. Trans. ix. 78--. t. i. f. 20.
[1536] Ibid. 55. t. i. f. 12.
[1537] This insect does not, I believe, eat the petals of the rose, but laps the nectar it produces. I have seen it employed upon wounded trees lapping the sap.
[1538] Mon. Ap. Angl. ii. 172. 257.
[1539] See above, p. 491, note^a.
[1540] Ibid. p. 219; and VOL. I. p. 267--.
[1541] Ibid. p. 256--.
[1542] Apis * *. e. 2. K.
[1543] Apis * *. c. 2. α. K.
[1544] Butterfly Collector's Vade Mecum, 66, note^d.
[1545] De Geer ii. 638--. 641--.
[1546] Swamm. Bibl. Nat. i. Conf. 114 with 103.
[1547] Reaum. vi. 480--.
[1548] VOL. II. p. 11.
[1549] Lepidopt. Britann. 263--.
[1550] Linn. Trans. v. 256.
[1551] VOL. II. p. 95--.
[1552] See above, p. 254--.
[1553] VOL. II. p. 217. See above, p. 200.