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fummer, and colds of the winter, and are never hatched till the fucceeding fpring ; and though thus expofed, it is ob- servable, that the fevereft winters do them no harm. Other fpecies of thefe are fooner hatched from the egg, and live the remainder of the fummer on the leaves of the tree. They, af- ter this, pafs the whole winter in the caterpillar ftate, ufually hiding themfelves in fome fheltered place, covered With webs of their own fpinning. Thefe remain torpid all the winter, and, at the return of fpring, leave their webs as the others do their eggs, and feed a few weeks longer, after which they pafs through the chryfalis ftate to their perfect form. The butterfly of this fpecies, therefore, enjoys a much longer time of life than the other which remains lb long in the egg ; tho' the ultimate duration of the animal, from its exclufion from the parent, till its death, is much the fame ; fo great a part of it being paffed in the egg ftate by the one, and fo fmall a part by the other. Reaumur, Hift. Inf. Tom. 2. Other fpecies of thefe animals remain the whole winter in the chryfalis ftate, and are butterflies in fpring, and, after paffing the middle of fummer in the egg, are caterpillars in the au- tumn. The difference of this ftage of life is remarkably great, in proportion to the whole duration of the animal j in fome fpecies it does not exceed a fortnight, and in others continues eleven months, Mr. Reaumur, however, tried the experi- ment of lengthening the lives of fome of thefe animals, by continuing them longer in their living ftate, and fucceeded in it, as well as in fhortening the general duration of others, by making their paflage out of the chryfalis earlier than it would naturally have been, and thefe, as fooh as they came out of this ftate, copulating, depofiting their eggs, and dying, the term of their total duration was made fhorter than the year. There is no fign of fex in the animal, while in the caterpillar ftate ; the propagation of the fpecies is the bufincfs of the creature in its ultimate perfection, and, till that, thefe parts are never excluded. One female butterfly, when file has been impregnated by the male, will produce three hundred or four hundred eggs, or even more. While the young ones, produced from thefe eggs, remain in the ftate of caterpillar, there is no union of the fexes, no inclination for it between them, nor any defires, except of food. But tho' the cater- pillar is cold in this refpect, the butterfly, or ultimate ftate oftheanimalj is as remarkably warm. Scarce is this crea- ture out of the (hell of the chryfalis, which, is as it were, its egg, fcarce are its wings dry enough for flight, before it mounts into the air to fcek the female. Its deiire of food is now no more, it has now no idea of eating, nor any organs for it; its whole defire is that of the propagating its fpecies. The moment it finds a female, it attacks her, and (he as rea- dily confents. From her, in a few minutes, he flics in fearch of another, thence to another, and fo on for his whole life ; all the fex being his concubines, and all ready to receive and love him.
There is no way of knowing the different fexes Of thefe little creatures, by viewing the parts; but the whole figure and manner of the animal makes the difference. The females arc always larger than the males ; they are alfo more flow in their motions ; and fome of them have no wings, or, at the ut- meft, only very fmall ones. The males, however, have a fort of beards, more beautiful than the autennse, or horns of the females ; the female is much ftroiiger; as well as bigger, than the male, and not unfrequently, at the approach of dan- ger or dilturbance, flys away with him in the time of copulation. Some join their bellies in the copulation, fome hold their bodies directly oppofite to one another ; and, in fome fpecies, the male all the time claps his wings, whereas in others he remains perfectly ftill. On differing the female, her uterus affords an aftonifhing fight ; the number of eggs in the tubes is amazing ; but thefe have not all the fame figure ; and in fome fpecies, as the filk worm, &c. the eggs are of a beautiful blue ; if any yellowifh ones are feen among them, they are judged to be defective. The outer covering of the egg is not a fhell, but a more tough and lefs hard fubftance, more rcfembling leather ; and there is ahnoft an infinite va- riety in their fhapes ; in fome fpecies they are round, in fome cylindric, in fome pyramidal, in others cylindric and ele- gantly ridged and ftriated ; in fome the furface is perfectly even and fmooth, and in others, befides thefe indentings, there are numerous little protuberances ufually of regular figures, and difpofed with perfect regularity. The care of all the butterfly tribe, to lodge their eggs in fafety, is furprifmg. Thofe whofe eggs are to be hatched in a few weeks, and are to live in the caterpillar ftate during part of the remaining fummer, always lay them on the leaves of fuch plants as they know will afford them a proper nourifhment ; but, on the contrary, thofe whofe eggs are to remain unhatched till the following fpring, foreknowing that the leaves of trees fall off in winter, always lay them on the branches of trees and fhrubs, and ufually are careful to felect fuch places as are leaft expofed to the rigours of the enfuing feafon, and fre- quently cover them from it in an artful manner. Some make a general coat of a hairy matter over them, taking the hairs from their own bodies for that purpofe ; others hide them- felves in hollow places in trees, and in other Ihcltered cells, and there live in a fort of torpid ftate the whole winter, that Sur.pL. Vol. I.
they rriay depofit their eggs in the fucceeding fpring, at z time when there will be no feverities of weather for them to combat. The day butterflies only do this, and of thofe but a very few fpecies ; but the night ones, or phalena:, all without exception,- lay their eggs as foon as they have been in copulation with the male, and die immediately after- wards. Reaumur, Hift. Inf. T. 2.
The Eructe furnifh us with an inftance of the falfity of that rule eftabliftied by moral writers, that man. is the only animal that deftroys his fellow creature, which, they fay, even the favages of the defarts fpare. It is a very certain truth, that many animals feed on the weaker of their own fpecies. '[ he pike, among fifh, is an inftance of it ; but nothing gives fo clear 'a view of it, as the examining thefe Jefler animals.
It is well known that the common and natural food of thefe creatures is the leaves and verdure of vegetables, yet as weak and harmlcfs as they feem, they will many of them deftroy their fellows whenever they get an opportunity. Reaumur gives us an inftance of this in twenty caterpillars of the oak, which he kept in a box, with a fufficicnt quantity of their natural food, yet their numbers daily decreased, till at length there remained only one.
He obferved that the manner of their preying an one another was this ; the ftrouger feized the weaker by the throat, and there giving him a mortal wound, left him to die at leifure, only watching him all the time; but as foon as he was dead, the murderer immediately began eating him, feeding upon the entrails and juices, and leaving only the ikin, with the head and feet. This is, however, only the cafe in fome few fpecies, the generality of thefe animals being very peaceable, and many fpecies living comfortably together in the fame place, without feeding upon, or at all molefting, one ano- ther. Thefe fpecies however, tho' freed from thele dangers, are expofed to others of a much more terrible kind ; the worms or maggots of feveral forts of flies are frequently found about them, fome preying upon their outfide; others lodged with- in them, under the fkin, but both kinds eating the poor de- feiicelefs creature up alive. Thofe which feed on the out- fides are eafily difcovered, the others are more hid, and fre- quently the caterpillar, which feems very hearty and vigorous, and very fleihy, (hall be found, upon opening, to be a mere fkin, the internal parts being all eaten away, and all the food that he (wallows ferving only to feed a vaft number of worms s or maggots, which crawl about at liberty within him. Thefe devouring worms are of many different fpecies, fome being of the gregarious, fome of the folitary kinds, and fome fpinning webs of their own filk to transform themfelves in, others undergoing that change without any fuch covering. The beautiful cabbage caterpillar is one of thofe unhappy kinds which frequently are infefted with the gregarious kinds, large numbers of which fpin themfelves webs one after another, and afterwards come out in the Ihape of the parent fly, to whofe egg they owed their origin. Reaumur, Hift. Inf.
VOL 2. p. I. p. 211.
Thefe inteftine enemies are a fure prevention of the butterfly's appearing at its proper time ; and as many of the former natu- ralifts, who knew what butterfly to expect from a peculiar fpecies of caterpillar which they preferved, often faw a parcel of flics come out in the place of it, they having no idea that the fly had laid its eggs in the flefti of the poor creature, fup- pofed that this was one of the natural transformations of the creature, and that certain fpecies of caterpillars fome- times produced butterflies, fometimes fmall flies. Goedart imagined that the poor caterpillar was fo careful for thefe its children, as to fpin them their filky bed, or covering, out of its own bowels.
Thefe, and many other deftroyers, among which the birds are to be reckoned in the principal place, ferve a noble pur- pofe in preventing the too great numbers of thefe mifchievous animals. Their ufual habitation being the leaves and flowers of plants, they are, in their feeding, much expofed to all thofe deftroyers ; yet nature has taken care to preferve a great num- ber, by making many of them fo exactly of the colours of the leaves they feed on, that they are not eafily diftinguifhed from them ; and by giving others a caution of keeping on the under part of the leaves, and being, by that means, out of fight. But fome fpecies arc much lefs expofed, and of much more nu'f- chief to the plants they feed on, by devouring more eflential parts of them. Of thefe fome eat the roots, and others the interior part of the trunk, deftroying the veflels that imbibe, and thofe that diftribute the juices. Thefe are different from, the common caterpillars, in that their fkin is much lefs, tough, and hard, and thefe are fecure from our observation, and, in general, from their great deftroyers the birds. They are not, however, abfolutely fafe from the common dan- gers of the other fpecies, for there are a kind of worms that find their food and habitation even in the bodies of thefe. Their habitations are the branches of the oak, elm, and poplar, when they begio to decay in the middle. They ufually lodge them- felves in the blea, and are able to pierce the hardeit wood when they have occaiion to change their habitation. Some of the Jargeft fpecies of caterpillars that we know of, live in this manner j and it may be known that they are in pofieflion of 10L a
