Chapter XIV: Letter XXXII: States of Insects (2)

Variations of the kind we are considering are also observable in the _clava_, or knob, in which antennæ often terminate. You have doubtless observed that the lamellated clava of the antennæ of the common cockchafer is much longer and more conspicuous in some individuals than in others--the long clava belongs to the male[802]. In another species, _M. Fullo_, that of this sex is nine or ten times the length of that of the other. In _Colymbetes serricornis_, a water-beetle, the male has a serrated clava of four joints. In _Dorcatoma dresdensis_[803], and also _Enoplium damicorne_, two beetles, it is nearly branched in the male, but much less so in the female. In a little destructive beetle, common in our houses (_Attagenus Pellio_), in the latter it is very short, but in the former it is very long, and nearly formed by a single joint. In _Eurhinus_ Kirby, a New Holland genus of the weevil-tribe, in the male the last joint, also, is much longer than it is in the female[804]. These examples will give you some idea of the principal variations that take place in the antennæ of the sexes, and of the wonderful diversity of forms in this respect to which mere sexuality gives rise amongst insects.

In the _eyes_, or _stemmata_, this diversity is less remarkable. Latreille has described two ants, _Formica contracta_ and _coeca_, in the neuter of which he could discover no eyes[805]: in the former, the female, however, had large ones. The male he appears not to have known, but it probably was not destitute of these organs; of the latter he was acquainted only with the workers. The neuter of _Myrmica rubra_, another ant, has no ocelli or stemmata, although the male and female are provided with them[806]. They are discoverable only in the former sex of that singular insect related to the ants, _Mutilla europæa_. Other insects differ in the _size_ of the eyes of their sexes. In the hive-bee, and some _Ephemeræ_, the eyes of the drone or male are much larger than those of the worker and female, and also meet at the vertex, having their stemmata below the conflux; whereas in these latter they are widely distant[807]. In _Stratyomis_, _Tabanus_, and many other two-winged flies, the _male_ eyes meet at some point below the stemmata, and above the antennæ. In the former they touch more at an angle; for the vertex forming a narrow isosceles triangle, and for the anterior part of the face one nearly equilateral: while those of the _female_ are separated by a considerable interval. In _Heptatoma_ and _Hæmatopota_ in that sex, a similar interval obtains; while in the other, after forming a minute short triangle, they unite for a considerable space, and then diverging, form the face. This is also the case in _Tabanus_; but in the female, the space that intervenes between the posterior part of the eyes is much narrower than in these two cognate genera of the horse-flies. In some others of this order, as _Musca_ Latr., the eyes of the male do not touch, but approach posteriorly much nearer to each other than those of the other sex. In a few instances the sexes vary even in the number of their eyes, as well as the size. This occurs in some species of _Ephemera_ L. (_E. diptera_, &c.), in which the male, besides the common lateral ones, has two large and striking intermediate eyes, that sit upon vertical pillars or footstalks[808].

2. The _Trunk_. The thorax of many coleopterous males, especially of the _Dynastidæ_ and _Copridæ_ amongst the petalocerous tribes, exhibits very striking differences from that of the female. In many _Lucani_ the lateral angle is more prominent. In _Anthia_ it is bilobed posteriorly, while in the last-mentioned sex it is entire[809]. In _Phanæus carnifex_ MacLeay (_Copris_ F.) it is elevated into a plane triangular space, with the vertex of the triangle pointing to the head; but in the female it is convex, with an anterior abbreviated transverse ridge[810].

In a large proportion terrific _horns_, often hollow, like those of the head lately noticed, arm the thorax of the male, of which you will usually only discover the rudiments in the other sex. In the first place, some are _unicorns_, or armed only with a _single_ thoracic horn, which frequently, in conjunction with the thorax itself, not a little resembles a tunnel reversed: of this description are _Dynastes Hercules_, _Tityus_, _Gedeon_, _Enema_, &c.[811] In the three first this horn is porrected, or nearly in the same line with the body; but in the last, and _D. Pan_, it forms an angle with it; and in _D. Ægeon_ it is nearly vertical[812]. In _D. Hercules_ it is very long; in _D. Alcides_[813] and _Tityus_ very short; in the two last, and in _Oxytelus tricornis_ which is similarly armed, it is undivided at the apex; but in _D. Gedeon_, _Pan_, _bilobus_, &c.[814] it is bifid or bilobed. It is usually rather slender, but in _D. Chorinæus_[815] and _bilobus_, it is very stout and wide. In _D. claviger_ it is hastate at the apex[816]. In _D. hastatus_ it is short and truncated[817]. Others, again, have _two_ thoracic horns. In _Copris nemestrinus_ these are discoidal, diverging, and inclining forwards[818]. In _Phanæus floriger_[819] they are lateral, triangular, and incline towards each other, with, as it were, a deep basin between them. In _P. splendidulus_ they sink into two longitudinal ridges, most elevated posteriorly, with an intervening valley[820]. In _P. bellicosus_ they are posterior, compressed, truncated, and emarginate at the apex, and include a basin[821]. In _Copris Sabæus_ they are merely two acute prominences[822].--_Three_ horns distinguish the thorax of many. In _D. Aloeus_[823] and its affinities, they are arranged in a triangle, whose vertex is towards the head. In _D. Antæus_[824] these horns are nearly equal in length, and undivided at the apex. In _D. Titanus_[825] the anterior horn is longer than the rest, and bifid at the apex; in _D. Atlas_ and _Endymion_[826], both of which have a horn on the head, it is much shorter. In others, as in _Megasoma_ Kirby, the vertex of the triangle is towards the anus. In _M. Typhon_[827] it is longer than the anterior ones, and bifid at the apex; in _M. lanigerum_ they are equal in length[828]. In _M. Elephas_ and _Actæon_[829] it is merely an elevation of the thorax; in the last almost obsolete. In _Geotrupes Typhæus_, common on our heaths, the anterior of this part is armed by three horizontal horns, the intermediate one being the shortest[830]. _Copris lunaris_ also, another of our own beetles, has three short posterior thoracic horns, two lateral and triangular ones, and a transverse intermediate elevation, with a notch in the middle[831]. In _Dynastes Neptunus_ the horns are porrected, the middle one being very long, and the lateral ones short[832]. In _D. Geryon_ the point of the lateral horns is towards the anus, and the base of the intermediate one covers the scutellum[833]. Others have _four_ of these singular arms: this is the case with one of our rarest beetles, _Bolbocerus mobilicornis_ K., which has four dentiform horns, the intermediate pair being the shortest, arranged in a transverse line on the anterior part of the thorax[834]. In _B. quadridens_ these are merely teeth. In _Phanæus Faunus_[835] it has two lateral, elongated, compressed, truncate, horizontal horns, and two intermediate teeth. _Dynastes Milon_ has a still greater number of horns on the thorax of the male, there being two lateral anterior ones and three posterior ones--the intermediate being the longest[836]; and _Copris Antenor_ Fabricius and Olivier describe as having a many-toothed thorax; and from the figure of the latter[837], the male appears to have seven prominences.

But the males of insects are not only occasionally distinguished by these dorsal arms--in a few instances they are also furnished with _pectoral_ ones. The illustrious traveller Humboldt found in South America a species of weevil (_Cryptorhynchus Spiculator_ Humb.), the breast of which was armed with a pair of long projecting horns; and I possess both sexes of four species, three at least from Brazil, that exhibit in one individual the same character. One, concerning the country of which I am uncertain, recedes somewhat from the type of form of the rest, and comes very near that of _Rynchænus Strix_ F.[838] In the individual which I take to be _C. Spiculator_, the pectoral horns are very long, curving upwards at the apex, and nearly in a horizontal position; while in the three others they are much shorter, and inclined towards the horizon. The males of some species of _Rynchites_, as _R. Bacchus_ and _Populi_[839], are also armed with a pair of lateral horns or spines, which may be termed pectoral rather than dorsal.

I shall now advert to the sexual characters that are to be found in the _instruments of motion_ attached to the trunk--beginning with those for _flight_. In the female of the common glow-worm (_Lampyris noctiluca_) not the slightest vestige of elytra or wings is visible, and it resembles a larva rather than a perfect insect; yet its mate is a true beetle furnished with both. The same circumstance distinguishes the female cockroach (_Blatta_) and is more universally prevalent in that genus than in _Lampyris_, in which a large number of females have both elytra and wings. The males of _Bombyx antiqua_ and _Gonostigma_, and of many other moths, have wings of the usual ample dimensions, while those of their females are merely rudiments. This is the case, also, with some of the _Ichneumonidæ_[840]. In the tribes of Ants, _Termites_, &c. the neuters or workers are without wings. Amongst the plant-lice (_Aphides_) there are individuals of both sexes, some of which have wings, and others not[841]. Amongst the _Coleoptera_, the female of _Tenebrio Molitor_, the common meal-worm, has elytra and no wings; while the male has both[842].--Sometimes these organs vary in size in the sexes: thus in _Aradus Betulæ_ F., a kind of bug, the hemelytra and wings are narrower and shorter in the female than in the male[843]. In the genus _Blaps_ F., the mucro that arms the apex of each elytrum is longer in the former sex than in the latter. In _Ateuchus gibbosus_ F., a dung-beetle, the elytra have a basal gibbosity near the suture in one sex that does not obtain in the other. In the _Orthoptera_ order, the sexes are often to be known, almost at first sight, by a difference in the veining and areolets of the wings; but upon this I enlarged so fully when I treated of the sounds produced by insects, that it is not necessary to repeat what I have said; which observation also applies to the drums which distinguish the male _Cicadæ_[844]. The wings of some butterflies, and of most moths and hawkmoths (_Sphinx_ L.), are furnished with a singular apparatus for keeping them steady, and the under-wing from passing over the upper in flight. This appears to have been first noticed by _Moses Harris_, and was afterwards more fully explained by _M. Esprit Giorna_[845]. From the base of the under-wing proceeds a strong bristle, received by an annulus or socket, which springing between the two principal nervures of the upper-wing terminates in the disk of the wing: in this annulus the bristle moves to and fro, and prevents the displacement of the under-wing. This apparatus is perfect only in the males, which alone have occasion for long flights; the females, though they have often several bristles, having no annulus[846].

The other instruments of motion, the _legs_, also differ in the sexes. In some instances they are disproportionably long. This is particularly the case with the _anterior_ pair of some beetles, as _Macropus longimanus_, _Scarabæus longimanus_ L., in which they are so long as to make the males of these individuals rather inconvenient in a cabinet. Amongst British beetles _Clytra longimana_ and _Curculio longimanus_ Marsh. are also remarkable in this respect. In some other males the _middle_ pair are the longest; as in _Anthophora retusa_ Latr., a kind of wild-bee[847]. There are two known instances of remarkably long _posterior_ legs in the Capricorn tribe, which I suspect belong to the present head. One is _Saperda hirtipes_ Oliv.[848], in which the hind-legs are longer than the whole body, and adorned with a singular tuft of hairs; and the other a _Clytus_, I think, which Mr. MacLeay purchased from the late Mr. Marsham's collection, in which the hind-legs are not only very long, but have tarsi convolute, like some antennæ. From analogy I should affirm that these were the characters of _male_ insects.

To come to the _parts_ of legs. Sometimes the _coxæ_ of the last mentioned sex are distinguished from those of the female by being armed by a _mucro_ or spine. Thus the male of _Megachile Willughbiella_, and others of that tribe, have such a spine on the inner sides of the anterior coxa[849]. The _Trochanter_ also of some differs sexually; and you will find that the posterior one of the male in _Anthidium manicatum_ is of a different shape from what it is in the female[850]. In _Sphodrus leucopththalmus_, one of the beetles called _black dors_, in one sex the same trochanter terminates in a long mucro or spine[851], and in the other it is rounded at the apex.

Peculiar characters in their _thighs_ also often indicate different sexes. In _Prionus damicornis_ there is a short spine at the apex of the _anterior_ ones in the female that is not in the male; while in _Macropus longimanus_, at their base externally the male is armed with a mucro, which I cannot find in the female[852]. In _Scarabæus longimanus_ L. this thigh is furnished with two teeth[853].--The _intermediate_ thighs also sometimes differ. In an _Onitis_ from China, a variety perhaps of _O. Sphinx,_ those in the male are dolabriform, and in the other sex of the ordinary shape. In _Odynerus spinipes_ they have on their lower side two sinuses, so as to give them the appearance of being toothed. The _posterior_ thighs are sometimes incrassated in the male, and not in the female. This you will see in a weevil, not uncommon, _Apoderus Betulæ,_ and also in many species of _Cimbex_ F., a kind of saw-fly; and the same circumstance distinguishes the latter sex in many species of _Lygæus_ F., a kind of bug: I discovered this from _L. cruciger_, of which I have both the sexes; and from Stoll's figure of _L. Pharaonis_[854]. In some of these the female thighs are enormously large. A remarkable variation in this respect is observable in the coleopterous genus _Œdemera_ (_Necydalis_ L.). In _Œ. Podagrariæ_ these limbs are incrassated in one sex and not in the other[855]; in _Œ. cærulea_ they are so in both sexes; and in _Œ. ceramboides_ in neither. In _Pelecinus Polycerator_ F., one of the Ichneumon tribe, or an insect very near it from Brazil, these thighs in the female are armed with two spines underneath, which are not in the male.

The _anterior tibiæ_ in _Scarabæus longimanus_ L. differ remarkably in the sexes. In the female they are of the ordinary shape, and serrated externally; but in the male they are very long, incurved, and without teeth or serratures[856]. In the males of the genus _Onitis_ F. they are bent like a bow, and acute at the end; but in the females they are formed on the common type[857]. In _Hispa spinipes_ F. they are armed internally with a crooked spine[858]. But the most extraordinary sexual variation of this joint of the leg may be seen in the male of _Crabro cribarius_ F. and several other species of the same family, in which these tibiæ are dilated externally into a concavo-convex plate, or rather have one fixed to them and part of the thigh, of an irregular and somewhat angular shape[859], with numerous transparent dots, so as not badly to resemble a sieve: whence the trivial name of the species. Rolander, who first described it, fancied that this plate was really perforated, and that by means of it the animal actually sifted the pollen; but it is most probably for sexual purposes. In another species, the plate is ornamented with transparent converging streaks. In the bee-tribes (_Anthophila_ Latr.) the _posterior_ tibia of the working sex is generally bigger than the corresponding part in their more idle partners: this is particularly conspicuous in the genus _Euglossa_, in the females of which this part is triangular, very broad towards the apex, and fitted for carrying a large mass of pollen paste. The tibiæ of the _males_ of some _Lepidoptera_ are remarkable in this respect. That of _Hepialus Humuli_ is much more hairy; but in _H. Hectus_ it is a dilated mis-shapen mass, without a tarsus, and with long scales pendent from the disk[860]. Differences of this kind also occur in the _calcaria_ or spurs that arm the apex of the tibiæ of a large number of insects. Thus in _Acanthopus_ Klug, a singular bee, in the male the spur of the intermediate leg is dilated at the apex, and armed with six strong spines, the inner one larger than the rest[861].

But the part of the leg in which the sexes most vary is the _tarsus_; and this variation takes place both in the number of the joints, and their form and circumstances. The first case has been observed only with regard to certain species of _Cryptophagus_ Herbst, as _C. fumatus_, &c. in which the female is _pentamerous_, or having _five_ joints in all the tarsi; and the male _heteromerous_, or having _five_ joints in the two _anterior_ pairs, and only _four_ in the _posterior_[862]. With respect to the form of the tarsal joints, the sexes more frequently differ; and by inspecting this part, especially in the predaceous and carnivorous _Coleoptera_, you may often, without further examination, ascertain whether any individual is male or female. Even in the slender-footed _Cicindelidæ_, the three first joints of the anterior tarsus of the male are more dilated than the two last, and covered underneath with a brush of stiffish hair; in the female all are equally slender, and not so hairy. In _Carabus_, _Feronia_, &c. Latr. the _four_ first joints of these tarsi in the males are dilated, and furnished with a brush or cushion: in the _Silphidæ_, also, the same circumstance takes place. In _Harpalus_ Latr., and _Silpha americana_, the _four_ anterior ones are similarly formed in this respect. But one of the most remarkable sexual characters, in this tribe of insects, that distinguish the males, are those orbicular patellæ, furnished below with suckers of various sizes, and formed by the three first joints of the tarsus, which are to be met with in the _Dytiscidæ_, &c.; but as I shall have occasion to treat of these more fully in another Letter, I shall only allude to them now. The second pair of tarsi have in these also the three first joints dilated and cushioned[863]. In _Hydrophilus piceus_, another water-beetle, the fifth joint of the tarsus is dilated externally, so as to form nearly an equilateral triangle[864]. Christian, a German writer on the _Hymenoptera_, has described some very singular appendages which he observed on the first joint of the four posterior tarsi of _Xylocopa latipes_ F. These were battledore-shaped membranaceous laminæ, with a reticulated surface, of a pale colour; which were fixed in pairs by the intervention of a footstalk to the above joint, on which they sometimes amounted to more than a hundred: the use of which, he conjectures, is the collection of pollen[865]. I possess two specimens of this bee; one has none of these appendages, and on the other I can discover them only in one of the tarsi--from which circumstance I am led to conjecture that, like the supposed _Clavariæ_ that were imagined to grow on some humble-bees, but which are now ascertained to be the anthers of flowers--these also belong to the kingdom of Flora, and are spoils which the bee in question has filched from the blossom of some plant. The individuals that have been thus circumstanced are males; whether the female is guilty of similar spoliations is not known. In my specimen there are no traces of them. In many bees, the first joint of the posterior tarsi is much larger in the females and workers than in the males; but in the hive-bee this joint is largest in the latter[866]. In _Beris clavipes_ and _Empis nigra_, two flies, the joint in question is large and thick in the male, but slender in the female. The penultimate tarsal joint in the posterior legs is dilated internally, and terminates in a mucro in one sex of _Anoplognathus Dytiscoides_ of Mr. W. MacLeay[867]. In some insects the anterior tarsus of the males has been supposed to be altogether wanting: I allude to the petalocerous genus _Onitis_ F.; but I have a specimen of _Onitis Apelles_ of this sex, or a species nearly related to it, in which one of these tarsi is to be found[868]; which, though very slender, consists of five joints, and is armed with a double claw: from which circumstance it may, I think, be concluded, that although, as in _Phanæus_, these tarsi are very minute, they are not wanting. What renders this more probable is, a circumstance which every collector of insects, who has many specimens of Mr. W. MacLeay's _Scarabæidæ_ in his cabinet, must have noticed: namely, that in all, except _Copris_ and _Onthophagus_, the anterior tarsi are usually broken off. Out of seventeen individuals of _Scarabæus_ MacLeay in my own, not a single one has a relic of an anterior tarsus; and scarcely one in a much greater number of _Phanæi_. The tarsus in question in the nobler sex in _Crabro_, at least in _C. cribrarius_ and its affinities, is also very short, especially the three intermediate joints; but at the same time very broad and flat. In the species just named, the external claw forms a kind of hook; and in the rest it is considerably longer than the other[869]. The _claws_, indeed, occasionally vary in the sexes in other _Hymenoptera_: thus in _Melecta_ Latr., a kind of bee, in the female they are intire, but in the male they are furnished with an internal submembranaceous tooth or process[870]. In _Cœlioxys conica_ and others, those of the latter sex are bifid at the apex, but those of the former acute[871]. In _Megachile_, the male claw is as in the instance just mentioned, while the female has a lateral tooth[872]; and a similar character distinguishes the sexes in the hive-bee[873].

3. The _abdomen_. This part affords many external sexual characters, whether we consider its general shape; the number of segments that compose it; its base, middle, or extremity.

In general _shape_ it often differs in the sexes. Thus, the abdomen of female _Tipulæ_ is lanceolate; that of the male cylindrical, and thickest at the extremity[874]. In _Molorchus_ F. it is convex above in the former, and flat in the latter,--the female of this beetle not unaptly representing some female _Ichneumons_ in this respect, and the male their males[875]. In _Andrena_ it is oblong in the one, and lanceolate in the other. In the hive-bee the drones have a thick, obtuse, and rather long abdomen; in the females it is long, and nearly represents an inverted cone; and in the workers a three-sided figure, or prism.

The _number of segments_, also, is generally different in the two sexes--the male having one more than the female; but in _Dytiscus marginalis_, &c. the reverse of this takes place: the female, if you reckon the bipartite half-concealed anal segment as one, having seven ventral segments, and the male only six. She has also eight dorsal, and the male seven.--In the ant tribes (_Formica_ L.), the little vertical scale, at the _base_ of the abdomen in one description of them, or the double knot in another, is less in the male than in the female. In a very singular male insect belonging to the _Vespidæ_, and related to _Synagris_, (which I purchased from the late Mr. Drury's cabinet,) the second ventral segment sends forth from its disk two remarkable parallel very acute and rather long spines. The same sex of _Chelostoma maxillosa_ has likewise on the same segment a concave elevation, opposite to which on the fifth is a cavity which receives it, when the animal rolls itself up to take its repose[876]. In another species, _C. Campanularum_, the segment in question has only a tubercle[877].

On the second segment of the abdomen of some specimens, probably males, of the remarkable African genus _Pneumora_ before alluded to[878], there are thirteen little elevated ridges, placed rather obliquely in an oblique series; and gradually, though slightly, diminishing in size towards the belly: on their upper side they are flat, forming nearly a horizontal ledge, but on the lower they slope to the abdomen. The posterior thigh in its natural position covers the three first of them, and, if moved downwards, would strike them all[879]. I conjecture, therefore, that these are the animal's instruments of sound, imitating the harp or violin rather than the drum; and that the thigh acts the part of the hand or bow. The abdomen of these insects being blown out like a bladder, and almost empty[880], must emit a considerable sound when the thigh of the animal passes briskly over these ridges; and their different length would produce a modulation in the sound. When struck with a pin, they emit a grating noise.

In _Staphylinus splendens_, the _penultimate_ ventral segment is very deeply cleft, and the antepenultimate emarginate in one sex, and intire in the other. In _S. laminatus_, an allied species, the penultimate segment is cleft, less deeply, however; but the antepenultimate is very short and intire; while the fourth is extremely long, and rounded at the margin, appearing as if it was only an elevated part of the last-mentioned segment; for which it was mistaken by Gravenhorst[881], while it is of the usual form in the other sex.

The _extremity_ of the abdomen or its _anal_ segments and organs furnish a variety of sexual characters. Sometimes the last dorsal segment is emarginate in the male, and not in the female; as in _Megachile ligniseca_, one of the leaf-cutter bees, _Cimex hæmorrhoidalis_, &c.[882] At other times little lateral teeth are added to this notch, as in another of the same tribe, _M. Willughbiella_[883]. Again, in other males, both the ventral and dorsal anal segment are armed each with a pair of teeth or mucros, as in _Chelostoma maxillosa_[884]. In _Anthidium manicatum_, another bee, the anus terminates in five spines[885]. In _Cœlioxys conica_ of the same tribe, in which this part in the female is very acute, that of the male is armed with six points[886]. In that singular Neuropterous genus _Panorpa_, while the abdomen of the female is of the ordinary form, with a pair of biarticulate palpiform organs attached to the last retractile joint, or ovipositor, that of the male terminates in a jointed tail, not unlike a scorpion's, at the end of which is an incrassated joint armed with a forceps[887]. In the common earwig (_Forficula auricularia_) the two sexes differ considerably in their anal forceps: in one it is armed with internal teeth at the base, and suddenly dilated, above which dilatation it is bent like a bow: in the other it is smaller, without teeth, grows gradually narrower, is very minutely crenulate from the base to the end, and is straight, except at the very summit, where it curves inwards. Misled by these and similar differences, Mr. Marsham has considered them (the sexes both of _F. auricularia_ and _F. minor_) as distinct species.

The tail of some species of the genus _Ephemera_ is furnished with three long, jointed, hairy bristles. We learn from Reaumur with respect to one, that though in the female these are all equal in length, yet in the male there is only a rudiment of the third. On the belly near the anus these males have four fleshy appendages, the posterior ones setaceous and long, and the anterior pair filiform and shorter. They are supposed to represent the anal forceps of other insects[888]. In _Ephemera vulgata_, described by De Geer, both sexes have three bristles, but those of the male are the longest; and he describes the forceps as consisting of only a pair of jointed pieces, forming a bow not unlike the forceps of an earwig[889].

v. All the differences I have hitherto noticed between the sexes of insects occur in their _bodily_ structure; but there are others of a somewhat higher description observable in their _character_. You may smile at the idea of character in beings so minute; but if you recollect what I formerly related to you when treating upon the societies of insects, you will allow that something of this kind does take place amongst them. In general the males are more fitted for locomotion and more locomotive; and the females, on the contrary, are necessarily more stationary. And this for an obvious reason:--the law is, that the male shall seek the female, and therefore he is peculiarly gifted for this purpose, both in his organs of sensation and motion: while his partner in many cases has very simple antennæ, he has very complex ones; and while she has either no wings or only rudiments of them, he is amply provided with them. Again: amongst the insects that suck the blood of man or beast, such as the gnat (_Culex_) or horse-flies (_Tabanidæ_), it is the female alone that is bloodthirsty, the males contenting themselves with the nectar of flowers[890]. But the difference of character in the sexes is most conspicuous, at least it has been more noticed, in those that live in societies, and is quite the reverse of what takes place in the human species. While the females and workers (which are now generally considered as sterile females, in which the ovaries are not developed) are laborious and active, diligent and skilful, wise and prudent, courageous and warlike;--the males, on the contrary, take no part in promoting the common weal, except merely a sexual one. Though till a certain period they are supported at the expense of the community, they take no part in its labours, either in collecting and forming the public stores, or in feeding and attending the young. They are idle, cowardly, and inactive; have neither art nor skill of any kind, and are unprovided with the usual offensive weapons of their species. These observations in their full force apply particularly to the hive-bee, and partially to the other social insects; amongst which, if you consult my former communications, there are some exceptions to this slothful character in the males[891].

II. _Age._ There is less diversity in the duration of the lives of insects in their perfect than in their larva or pupa state. Some, like several species of _Ephemeræ_, live only a few hours; some never even see the sun[892]: others, as flies, moths, and butterflies, and indeed the majority of insects, a few days or weeks; and a comparatively small number, such as some of the larger _Coleoptera_, _Orthoptera_, &c., six, nine, twelve, or fifteen months--a period beyond which the life of perfect insects rarely extends. Some, however, certainly enjoy a longer existence in the perfect state. Mr. Baker kept one of the darkling beetles (_Blaps Mortisaga_) alive under a glass upwards of three years. The rose-beetle (_Cetonia aurata_), Rösel informs us he fed with fruit and moist white bread for as long a period[893]. Esper kept our most common water-beetle (_Dytiscus marginalis_) in water in a large glass vessel, feeding it with meat, for three years and a half[894]. With regard to the _Arachnida_, from the very slow growth of _Scorpio europæus_, Rösel suspects that it must live two or three years; and Audebert is stated to have kept a spider for several[895]. In this respect insects follow a law very different from that which obtains amongst vertebrate animals. In these the duration of their life is in proportion to the term of their growth: those which attain to maturity the latest, in almost every case living the longest. In insects, on the contrary, we often meet with the very reverse of this rule. Thus the larva of the great goat-moth (_Cossus ligniperda_) is three years, that of the cabbage-butterfly (_Pieris Brassicæ_) not three months, in attaining maturity; yet the perfect insects live equally long. _Melolontha vulgaris_, which in its first state lives four years, as a beetle lives only eight or ten days[896]. And some _Ephemeræ_, whose larvæ have been two years in acquiring their full size, live only an hour; while the flesh-fly, whose larva has attained to maturity in three or four days, will exist several weeks.

There is yet another anomaly in the duration of the life of perfect insects. This is not, as in larger animals, a fixed period liable to be shortened only by accident or disease, and incapable of being prolonged; but an indeterminate one, whose duration is dependent on the earlier or later fulfilment of a particular animal function--that of propagation. The general law is, that a few days, or at most weeks, after the union of the sexes, both perish, the female having first deposited her eggs. If, therefore, this union takes place immediately after the disclosure of the insect from the pupa, their existence in the perfect state will not exceed a few _days_ or _weeks_, or in some cases _hours_, as in that of the _Ephemera_, and likewise of the _Phalænæ Attaci_ L. &c., which fall down dead immediately after oviposition[897]. But if by any means it be put off or prevented, their life may be protracted to three or four times that period. Gleditsch asserts, that by keeping apart the sexes of a grasshopper, their lives were prolonged to eight or nine weeks, instead of two or three, their ordinary length; and under similar circumstances _Ephemeræ_, which usually perish in a day, have been kept alive seven or eight. It is in consequence of this very curious fact, which has not received from physiologists the attention that it merits, that many butterflies and other insects, which, when excluded from the pupa in summer, perish in less than a month, live through the winter, if excluded late in the autumn, and the union of the sexes does not ensue. It is probable that the great age to which Baker's _Blaps_, Rösel's _Cetonia_, and Esper's _Dytiscus_ attained, was owing to their being virgins when taken, and subsequently kept from any sexual intercourse. A parallel case happens in the vegetable kingdom:--if annual plants are kept from seeding, they will become biennial; as, likewise, if they are sown too late in the year to produce seeds.

In the case, however, of the earlier or later exclusion of the imago, another agent has probably some influence. Buffon found that, other circumstances being alike, the silkworm-moths placed in a _northern_, lived longer than those exposed to a _southern_ aspect: whence it appears that the stimulus of heat shortens the lives of insects, and consequently that cold tends to lengthen them.

It must be observed too, that as the death of the female insect does not take place until all the eggs are excluded, the term of her life, though usually short in the majority of species, which lay their whole number at once, is proportionably long in those which, like the queen-bee, have a longer period assigned them for this important office. Huber affirms, that he had certain proofs that she was engaged for two years in laying eggs, all impregnated by a single sexual union[898]; and in the females of most insects that live in society, several months are required to mature the last eggs that are in the ovary. There is one tribe of insects, however, the females of which are affirmed to survive this operation: I mean _Dorthesia_ Bosc; after which they even moult, though not so often as before[899].

I formerly related to you the singular fact, that the drones in a beehive at a certain period are without mercy slaughtered by the workers[900]. A fact the reverse of this is recorded by Morier with respect to the locusts: he affirms that the female, when she has done laying her eggs, is surrounded and killed by the males. He says that he never himself witnessed this extraordinary circumstance; but that he heard it from such authority that he gave full credit to it[901]. It is a fact, however, that seems to require further evidence to entitle it to such credit. These are instances in which, by a law of nature, the life of these insects is shortened by violence. It does not appear to have been ascertained how long those drones live that, under particular circumstances, as stated in a former letter[902], are exempted from the usual slaughter.

I am, &c.

FOOTNOTES:

[683] See above, VOL. II. p. 346.

[684] Reaum. i. _Mem. ult._ De Geer i. 73. Swamm. _Bibl. Nat._ i. 184.

[685] Swamm. _Ibid._

[686] Jurine _Hymenopt._ 16.

[687] iv. 342. Herold also attributes the rapid expansion of the wing to the flow of an aqueous fluid, which he calls _blood_, into the nervures, the orifices of which open into the breast. _Entwickelungs. der Schmetterl._ 101. sect. 106.--M. Chabrier, in his admirable _Essai sur le Vol des Insectes_ (_Mém. du Mus._ 4ieme, ann. 325), having observed a fluid in the interior of the nervures of the wings of insects, thinks it probable that they can introduce it into them and withdraw it at their pleasure: the object of which, he conjectures, is either to strengthen them and facilitate their unfolding, or to vary the centre of gravity in flight, and increase the intensity of the centrifugal force.

[688] _Ibid._ 340.

[689] Brahm. _Insek._ ii. 423.

[690] Reaum. vi. 505--. _t._ xlvi. _f._ 9. Comp. De Geer ii. 627--.

[691] Reaum. iii. 378.

[692] Ibid. 385.

[693] Insects of the beetle tribe, especially such as undergo their metamorphosis under ground, in the trunks of trees, &c., are often a considerable time after quitting the puparium before their organs acquire the requisite hardness to enable them to make their way to the surface. Thus, the newly-disclosed imago of _Cetonia aurata_ remains a fortnight under the earth, and that of _Lucanus Cervus_, according to Rösel, not less than three weeks.

[694] See above, VOL. I. p. 34--.

[695] Jurine _Hymenopt._ 9. Note 1.

[696] Oliv. N. i. _t._ i. _f._ 1. _c. f._ N. 3. _t._ iii. _f._ 22. _a b c._ _t._ v. _f._ 33. _t._ vi. _f._ 5. _t._ xiii. _f._ 124. _a b._

[697] Reaum. vi. 423.

[698] Kirby Mon. _Ap. Angl._ ii. _t._ xvi. _f._ 12, 13. _t._ xvii. _f._ 10-12.

[699] Reaum. iv. 393.

[700] See above, VOL. I. 473--.

[701] De Geer vii. 304.

[702] Reaum. iv. 30.

[703] Ibid. _t._ iv. _f._ 15.

[704] See above, VOL. II. 36.

[705] De Geer iii. 25.

[706] _Linn. Trans._ iv. 54--.

[707] ix. 65. _n._ 110.

[708] vi. 423.

[709] _Entomologische_, &c. 224.

[710] De Geer ii. 847. 850. Jurine _Hymenopt._ 100.

[711] Kirby _Mon. Ap. Angl._ ii. 296. 264.

[712] _Ibid._ ii. 142--. 144, 147, 148, &c.

[713] A remarkable anomalous exception to this rule sometimes occurs in the female of _D. marginalis_, which has smooth elytra like the male (Gyll. _Ins. Suec._ i. 467-). I have this variety from the Rev. Mr. Dalton, of Copgrove, Yorkshire.

[714] De Geer i. _t._ vii. _f._ 11.

[715] See above, VOL. II. 125, Note^b.

[716] _Melitta_ ** c. Kirby _Mon. Ap. Angl._ i. 140.

[717] _Ibid._ _t._ iv. _f._ 10. _a. b. f._ 14.

[718] _Ibid._ _t._ xiii. _f._ 20. _a._

[719] Kirby _Mon. Ap. Angl._ i. _t._ xi. Apis **. d. 2. α. β. _f._ 18 _a. b. c. d._

[720] Coquebert _Illustr. Icon._ i. _t._ vi. _f._ 6.

[721] Kirby _Mon. Ap. Angl._ i. _Apis_ **. _c._ 1. α. **. c. 1. β. **. c. 2. α. **. c. 2. β. **. c. 2. γ. **. c. 2. δ.

[722] _Ibid._ _t._ viii. _f._ 28. _f. g._

[723] Christ. _Hymenopt._ _t._ iv. _f._ 3. _b._

[724] Kirby _Mon. Ap. Angl._ i. _t._ iv. _Melitta_ **. c. _f._ 1. _a._

[725] Scheven _Naturfors._ stk. xx. 65. _t._ ii. _f._ 4. Compare _Ibid._ x. 101.

[726] Reaum. iii. _t._ xv. _f._ 18, 19.

[727] Oliv. no. 84. _Brentus_, _t._ i. _f._ 1. _b. c. t._ ii. _f._ 17. _a. b._

[728] Oliv. no. 3. _Scarabæus_, _t._ xviii. _f._ 169.

[729] Oliv. _Scarabæus_, _t._ xii. _f._ 114. _t._ xv. _f._ 138. _a._

[730] _Ibid._ _t._ v. _f._ 33.

[731] _Ibid._ _t._ xii. _f._ 112.

[732] _Linn. Trans._ vi. _t._ xix. _f._ 12. _t._ xx. _f._ 2.

[733] Oliv. no. 57. _Tenebrio_, _t._ i. _f._ 2.

[734] Oliv. _ubi supr._ No. 3. _t._ i. _f._ 1.

[735] Oliv. no. 3. _t._ iii. _f._ 20. _a._

[736] Ibid. no. 55. _Diaperis_, _t._ i. _f._ 3.

[737] Oliv. _Scarabæus_, _t._ xx. _f._ 185.

[738] As _Dynastes Actæon_, _Elephas_, _Typhon_, &c. differ from _D. Hercules_, &c., not only in their general habits, horns, &c., but also in their maxillæ and labium,--the former in _D. Actæon_ being simple, and in _D. Hercules_ toothed, and the labium of the first bilobed at the apex, and in the last entire and acute,--according to the modern system they ought, therefore, to be considered as distinct genera. I would restrict the name _Dynastes_ to _D. Hercules_ and its affinities: _D. Actæon_, &c. I would call _Megasoma_.

[739] Oliv. _Scarabæus_, _t._ xvii. _f._ 156.

[740] _Ibid._ _t._ viii. _f._ 63.

[741] This insect is beautifully figured in M. Latreille's _Insectes sacres des Egyptiens_, _f._ 11. See Luke xi. 15. Heb. בעלןבול _Dominus stercoris_.

[742] Oliv. no. 83. 160. _t._ vi. _f._ 60. ♂. _t._ v. _f._ 45. ♀?

[743] _Ibid._ no. 36. _t._ ii. _f._ 12.

[744] _Ibid._ no. 6. _t._ vii. _f._ 61.

[745] See above, VOL. II. 224--.

[746] Coquebert _Illustr. Icon._ iii. _t._ xxi. _f._ 2.

[747] Stoll _Cigales_, _t._ xviii. _f._ A B C. _Grillons_ _t._ iv. _f._ 16-18. This singular animal, which was found by Mr. Patterson at the Cape of Good Hope, is stated to be an _aquatic_; and affords the only known instance of an _Orthopterous_ insect inhabiting the waters. The _Gryllotalpa_ loves the vicinity of water.

[748] _Mon. Ap. Angl._ i. _Melitta_ **. b. 139. _t._ ii. _f._ 4-6.

[749] _Ibid._ **. a. _f._ 4, 5.

[750] _Ibid. Apis_ *. b. 190--. _t._ v. _f._ 18 _b._

[751] By Rösel, by a friend of De Geer's, and by M. Marechal. De Geer iv. 331--. _Nouv. Dict. d'Hist. Nat._ xviii. 225.

[752] Oliv. no. i. _Lucanus_, _t._ ii. _f._ 3.

[753] _Ibid._ _t._ iii. _f._ 7.

[754] _Linn. Trans._ xii. 410. _t._ xxi. _f._ 12.

[755] _Ibid._ vi. 185. _t._ xx. _f._ 1.

[756] Oliv. _ubi supr._ _t._ ii. _f._ 4.

[757] _Regne Animal_, iii. _t._ xiii. _f._ 3.

[758] See VOL. I. PLATE I. FIG. 3.

[759] Christ. _Hymenopt._ _t._ xviii. _f._ 2.

[760] _Mon. Ap. Angl._ i. _Melitta_ *. a. _t._ i. _f._ 5. ♀. 7. ♂.

[761] _Ibid._ _Melitta_ **. a. _t._ ii. _f._ 6. ♀. 7. ♂. and **. b. _t._ iii. _f._ 3. ♀. 4. ♂.

[762] _Ibid._ _t._ viii. _f._ 11. ♀. 12. ♂.

[763] _Ibid._ i. _t._ viii. _f._ 9. ♀. 10. ♂.

[764] _Ibid._ _Apis_ **. c. 2. β. _t._ ix. _f._ 6. ♀. 7. ♂.

[765] See above, VOL. II. 125. Note^b.

[766] _Mon. Ap. Angl_. ubi supr. _t._ xiii. _f._ 13. ♀. 14. ♂.

[767] MacLeay _Hor. Entomolog._ 4--.

[768] _N. Dict. d'Hist. Nat._ xxii. 488.

[769] _Linn. Trans._ xii. 425--. _t._ xxii. _f._ 6.

[770] PLATE XXVI. FIG. 2.

[771] _Ibid._ FIG. 3.

[772] Oliv. no. xxv. _Lymexylon_, _t._ 1. _f._ 1.

[773] De Geer vii. 249--. _t._ xiv. _f._ 20, 21. Treviranus _Arachnid._ 36--. _t._ ii. _f._ 16. _a b c._ _t._ iv. _f._ 35-37.

[774] _Mon. Ap. Angl._ i. Apis **. c. 2. γ. _t._ ix. _f._ 7. ♀. 9. ♂.

[775] _Ibid._ _Melitta_ **. a. _t._ ii. _f._ 8. ♀. 9. ♂. and **. b. _t._ iii. _f._ 6. ♀. 7. ♂. **. c. _t._ iv. _f._ 11. ♀. 12. ♂.

[776] Jurine _Hymenopt._ _t._ 11. _f._ 2.

[777] _Mon. Ap. Angl._ i. Apis **. d. 1. _t._ x. _f._ 7.

[778] Oliv. no. 80. _Macrocephalus_, _t._ i. _f._ 2.

[779] Latr. _Gen. Crust. et Ins._ iv. 156.

[780] Jurine _Hymenopt._ 61. _t._ vi. _f._ 8.

[781] Ibid. 289.

[782] _Mon. Ap. Angl._ i. _t._ ix. Apis **. c. 2. γ. _f._ 9.

[783] PLATE XI. FIG. 19.

[784] PLATE V. FIG. 3.

[785] PLATE XI. FIG. 18.

[786] Ibid. FIG. 17.

[787] PLATE XXV. FIG. 11. _Linn. Trans._ xii. _t._ xxi. _f._ 4. _a._

[788] _Ibid._ _f._ 3.

[789] PLATE XXV. FIG. 22.

[790] De Geer i. _t._ xix. _f._ 11, 12.

[791] Jurine _Hymenopt._ _t._ vi. _f._ 8.

[792] PLATE XXV. FIG. 25, 26.

[793] Ibid. FIG. 4.

[794] Reaum. iv. _t._ xl. _f._ 2. _a a._ ♂. _t._ xxxix. _f._ 3. ♀. In the last the hairs are too conspicuous.

[795] PLATE XII. FIG. 24.

[796] Jurine _Hymenopt._ _t._ vi. _f._ 3.

[797] PLATE XII. FIG. 25, 26. XXV. FIG. 17, 32.

[798] Ibid. FIG. 12.

[799] PLATE XI. FIG. 22.

[800] _N. Dict. d'Hist. Nat._ xiv. 395.

[801] PLATE XII. FIG. 7.

[802] PLATE XXV. FIG. 1.

[803] Ibid. FIG. 21.

[804] _Linn. Trans_. xii. _t._ xxii. _f._ 8. _e._ ♂. _f._ ♀.

[805] _Hist. Nat. des Fourmis_, 195--. 270--.

[806] De Geer ii. 1094.

[807] Ibid. 650. _Mon. Ap. Angl._ i. _t._ xi. _Apis_ xx. _c._ 1. _f._ 2. ♂. _t._ xii. _f._ 3. ♀.

[808] PLATE XXVI. FIG. 39. De Geer ii. 651. 659.

[809] Voet _Coleopt._ i. _t._ xxxix. _f._ 47, 48. ♂. 46. ♀.

[810] Oliv. no. 3. _t._ vi. _f._ 46. _a._ ♂. _b._ ♀.

[811] Ibid. _t._ i. _f._ 1. iv. x. _f._ 31. xi. _f._ 102. xii. _f._ 114.

[812] Ibid. _t._ xxvi. _f._ 219.

[813] Ibid. _t._ i. _f._ 2.

[814] Ibid. _t._ xxiii. _f._ 35.

[815] Ibid. _t._ ii. _f._ 7.

[816] Ibid. _t._ v. _f._ 40.

[817] Ibid. xix. _f._ 175.

[818] Ibid. _t._ xii. _f._ 115.

[819] _Copris floriger_ Kirby in _Linn. Trans._ xii. 396.

[820] Oliv. no. 3. _t._ ii. _f._ 18.

[821] Ibid. _t._ xxii. _f._ 32.

[822] Ibid. _t._ ix. _f._ 85.

[823] Ibid. _t._ iii. _f._ 22.

[824] Ibid. _t._ xiii. _f._ 124. _a._

[825] Ibid. _t._ v. _f._ 38.

[826] Ibid. _t._ xxviii. _f._ 242. _t._ xviii. _f._ 169.

[827] Ibid. _t._ xvi. _f._ 152.

[828] Ibid. _t._ xxviii. _f._ 247.

[829] Ibid. _t._ xv. _f._ 138. _a. t._ v. _f._ 33.

[830] Samouelle's _Compend._ _t._ i. _f._ 1.

[831] Oliv. no. 3. _t._ v. _f._ 36. _a._

[832] _Schon. Synon._ i. _t._ 1.

[833] Oliv. no. 3. _t._ xxiv. _f._ 208.

[834] Ibid _t._ x. _f._ 88.

[835] Ibid. _f._ 87.

[836] Ibid. _t._ xx. _f._ 185.

[837] Ibid. _t._ vi. _f._ 42. _a._

[838] Ibid. n. 83. _Curculio_ _t._ xxii. _f._ 295.

[839] Oliv. no. 81. _Attelabus_ _t._ ii. _f._ 27. _b._ 28.

[840] De Geer ii. _t._ xxxi. _f._ 18-22.

[841] Ibid. iii. 21.

[842] Lesser L. i. 185.

[843] De Geer iii. 308.

[844] See above, VOL. II. 394--.

[845] _Linn. Trans._ i. 145. 135--.

[846] _Ibid._ _t._ xiii. _f._ 1. 2. ♂. 3. ♀.

[847] _Mon. Ap. Angl._ i. _t._ xi. Apis **, a. 2. α. β. _f._ 18.

[848] Oliv. no. 68. _Saperda_ _t._ i. _f._ 8.

[849] _Mon. Ap. Angl._ i. _t._ viii. _f._ 28. _c._

[850] _Ibid._ _t._ ix. Apis **. c. 2. β. _f._ 12.

[851] Clairv. _Ent. Helv._ ii. _t._ xii. _f._ B.

[852] Oliv. _Ins._ no. 66. _t._ iii. iv. _f._ 12.

[853] Ibid. no. 3. _t._ iv. _f._ 27.

[854] _Punaises_, _t._ iii. _f._ 20.

[855] Mr. Marsham has made two species of this from this circumstance, viz. _Necydalis Podagrariæ_ and _simplex_.

[856] Oliv. n. 3. _t._ xxvii. _f._ 27. ♀. and _t._ iv. _f._ 27. ♂.

[857] Ibid. _t._ vii. _f._ 58. ♂. _f._ 57. ♀.

[858] Ibid. n. 95. _Hispa_ _t._ i. _f._ 4. PLATE XXVII. FIG. 24.

[859] PLATE XV. FIG. 3.

[860] De Geer i. _t._ vii. _f._ 14, 15.

[861] Coquebert _Illust. Icon._ i. _t._ vi. _f._ 6. PLATE XXVII. FIG. 32.

[862] Illig. _Mag._ iv. 214. Gyllenhal. _Insect. Suec._ i. 168.

[863] PLATE XV. FIG. 9.

[864] Ibid. FIG. 8.

[865] Christ. _Hymenopt._ 118. _t._ iv. _f._ 3.

[866] _Mon. Ap. Angl._ i. _t._ xi. _Apis_ **. e. 1. ♂. _f._ 8. _e._ and _t._ xii. **. e. 1. neut. _f._ 19. _c._

[867] _Hor. Entomolog._ 144.

[868] PLATE XXVII. FIG. 45. _a._

[869] De Geer ii. _t._ xxviii. _f._ 2.

[870] _Mon. Ap. Angl._ i. _t._ v. _Apis_ **. a. _f._ 10. ♂. 11. ♀.

[871] _Ibid._ _t._ vii. Apis **. c. 1. α. 17. ♀. 18. ♂.

[872] _Ibid._ _t._ viii. _f._ 30. ♂. 31. ♀.

[873] _Ibid._ _t._ xi. Apis **. e. 1. mas. _f._ 9. _t._ xii. Apis **. e. 1. fem. _f._ 9. and neut. _f._ 22.

[874] De Geer vi. _t._ xviii. _f._ 12, 13.

[875] De Geer v. 151--.

[876] _Mon. Ap. Angl._ i. 177. _t._ ix. Apis **. c. 2. γ. _f._ 11. _a_, _d_.

[877] _Ibid._ _f._ 13. _a._

[878] See above, VOL. II. 395.

[879] PLATE XXIX. FIG. 13. Stoll. _Spectres_, &c. _t._ xxv. _f._ 99.

[880] Sparrman. _Voyage_, i. 312--.

[881] _Coleopt. Micropt._ 16.

[882] _Mon. Ap. Angl._ i. _t._ viii. _f._ 25. De Geer iii. 255. _t._ xiv. _f._ 8.

[883] _Mon. Ap. Angl._ i. _t._ viii. _f._ 24.

[884] _Ibid._ _t._ ix. Apis xx. c. 2. γ. _f._ 12.

[885] _Ibid._ Apis **. c. 2. β. _f._ 11.

[886] _Ibid._ _t._ vii. Apis **. c. 1. α. _f._ 11, 12. ♀. 13, 14. ♂.

[887] PLATE XV. FIG. 12. De Geer ii. _t._ xxiv. _f._ 9, 10. ♀. _t._ xxv. _f._ 2, 3. ♂.

[888] Reaum. vi. 494. _t._ xliv. _f._ 3-11.

[889] De Geer ii. _t._ xvii. _f._ 5-7.

[890] _N. Dict. d'Hist. Nat._ xxxii. 443.

[891] See above, VOL. II. 110, 118.

[892] VOL. I. 283.

[893] II. i. 6.

[894] Clairville _Ent. Helvet._ ii. 214--. I have seen it asserted in some popular work on _Natural History_, (the title of which I do not recollect,) that _Mantis religiosa_ has been known to live ten years; and a _flea_, when fed and taken care of, six. But this is so contrary to experience in other cases, that the statement seems quite incredible.

[895] Rösel III. 379. _N. Dict. d'Hist. Nat._ ii. 285.

[896] Dumeril _Traité Elément._ ii. 87. n. 683.

[897] De Geer ii. 288.

[898] Huber i. 106.

[899] _N. Dict. d'Hist. Nat._ ix. 553.

[900] VOL. II. 173--.

[901] Morier's _Second Journey through Persia_, 100.

[902] VOL. II. 175.