wood. These pincers, in fome infects, are exceedingly fmooth and fhining; they pretty much resemble the fpur of a cock, as may be seen in the larva of the Hemerobius. Some have fmall teeth on the fide of those parts which form the pincers, and oppofite to one another. They are not broad like thofe in man, but pointed and curved, nearly like the teeth of a faw. Their number is not equal. Beetles have two: Scolopendra three, and the larvæ of dragonflies fix. The maxillæ of fome infects have at their base two fingular knobs, with a longitudinal recefs, into which the maxillæ can be folded, like the blade of a clafp-knife. When the infect would feize any thing, and for that purpofe joins the two pieces of these pincers, they do not touch, in fome infects, except at the points; in others, which have them longer, they fold over each other.

These pincers are of great ufe to them; ferving them not only inftead of teeth, in breaking and comminuting the food they take, but for grinding many other fubftances, according to their neceflities. It is with these they feize their prey, and hold it fast. They are likewife arms both offenfive and defenfive. Those which make holes in the ground, employ them in removing the things that abftruct their progrefs.

There are fome infects of prey, (for they well deferve the name,) which, befides thefe pincers, have, at the mouth a fort of claws, with which they hold their booty, as birds of prey hold theirs with their feet. Others likewife have jaws (maxilla) fituated under the pincers, which are moveable, like them, but in a lefs degree.

I must not in filence pafs over the trunk, or, as others call it, the tongue of infects. Some, as the grafshoppers, carry it between their pincers. There

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are fome that can extend and draw it in at pleasure The Lepidoptera roll it up very adroitly, between two bearded bodies that conceal and protect it: others place it along their abdomen, where there is a little furrow formed for its reception. This trunk is not always of equal length: fome have it very fhort, and fome longer than the whole body. When it is viewed through a microscope, it is found to be very curiously fabricated, and, in a manner, adapted to the way of life of the particular infect: All its parts are fo difpofed, that nothing is fuperfluous, nothing deficient. In fome, it is inclofed in a fort of fheath, which terminates in a very acute point, ferving to pierce the substances that contain their food. When they have done this, they open the fheath, and infert the trunk into the wound, that they may extract the juice. It ferves, therefore, as a fyphon to fuck the fluids they ufe as aliment. And befides this, it

ferves to prick, and to wound like a lancet. Though this trunk is fo fmall that it can hardly be perceived, except it be with a glass, it is, nevertheless, fo hard, that it can pierce, without difficulty, the hardest and thickest hide.

After the head, there follows the neck, the thorax and lastly the abdomen. The thorax is more or less hard in proportion as the habits of the infect expose it to a greater or lefs degree of attrition. Those which creep into clefts as the Cimices, have this part of the body fomething flat, that they may the more eafily penetrate. It is more rounded in others, and fome, like the Silphas, have it furnished with elevated margins, occafioning a pretty confiderable correfponding furrow. The thorax in fome terminates in a point behind, and that of others is blunt or rounded, as in grafshoppers.. Many have it fet with hairs, and others with minute elevations which defend it from the effects of violent friction. It is furmount

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ed in fome with a protuberance, with two angles, with a horn, or with bodies of a pyramidical or thomboidal figure.

In the abdomen of infects there are many things which merit attention; and in the first place those incifures from which thefe animals derive their name. Thefe are called rings or articulations; they are formed with great art, and very much differ in appearance. Some are very clofe, and look like wrinkles, others are broad and long: fome are square and fome are furnished with a margin or rim; and often there is an opening difcoverable between the folds. All infects, as may be easily imagined, have not the fame number of these rings. Some have five, some fix, and fome feven; all caterpillars have ten, and the aphides of the cabbage twelve. Some Scolopendræ have twenty, fome forty or fifty, and a certain larva of a Tenthredo feventy-two.

Thefe rings are of effential ufe to infects. It is by extending and contracting thefe that they move. By contracting them they defend the delicate parts of their internal frame from the heat of the Sun, from rain and from wind.. If they need heat or refreshment, they can procure either the one or the other by the dilatation of their rings which then allow a free paffage to the rays of the Sun, or the fresh air. As they can dilate themselves at pleasure they can receive the precife quantity of either they have occafion for.

There is fuch diverfity of figure in the bodies of infects and they are fo wonderfully formed that an exact defcription of them would be impoffible. The body of fome, as the spider, is of a spherical fhape, that of others as the cocinella, is hemifpherical. Some are round and flat, as the pediculi of the bat, others

are oval; fome have the figure of an egg compref fed, and fome refemble the quill of a feather. Some have the body flat and fquare. The body of the infect called Hippocampus has four long and flat fides; that called the Corculum aquaticum is of the figure of a heart. Some are crooked like a hook, and are furnished with a long tail, or fmall bag at the pofterior extremity; of this laft the Sphex fabulofa is an example. The diverfity of colour in this part is nor lefs remarkable, but we fhall enter more minutely into this fubject hereafter.

Thofe infects which have no feet have in different places of their body, fmall points which ferve instead of them; and with these they attach themselves to folid bodies, and keep faft to them. In horfe dung there is to be found a maggot about an inch in length, whofe body has nearly the figure of a cherry-ftone. This animal has fix rings by means of which it can elongate and contract itfelf like the pipe uted in fome places for decoying' quails; the furface of each of these rings is garnifhed with fmall acute points; in fuch a manner that when the maggot chufes to raise them up, they penetrate the bowels of the horfe, and keep the infect fo firm, that it is not carried along with the faces.

The bodies of thofe infects which live in water pare naturally covered with a fort of oil which prevents the water from adhering to them, and retarding their motion. Others have along their body fmooth or crenulated margins, fometimes knobs that not only ferve to preferve them from being hurt by attrition upon entring or going out of their holes, but alfo are an ornament. Thefe are not quite fo large as a grain of millet, yet there is obfervable an affemblage of the moft beautiful colours, and they refemble thofe little glafs balls filled with different co

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foured waters. Laftly fome like the camel have a protuberance on their back.

But we fhall find as much diverfity in the parts that remain as in those we have already mentioned. The extremity of the abdomen is not alike in all. Some have it fmooth, in others it is fet with hairs, longer or fhorter according to the ufes they are def tined for. In this place are fituated the papillæ from which they draw the threads they use in their different webs. Some like the caterpillar of the Phalæna bucephala have this part covered with a fhort of fhield, Others have at the fame place a stiff membrane which affifts them as a rudder to turn when flying to this fide or that; and is to infects what the tail is to birds. Some have long fender briftles, one, two, three, or four; and others a fort of horns, ftraight, bent or crooked in various infects. When thefe horns are touched, fome like the caterpillar of the Sphinx Euphorbia can draw them in as fnails do theirs. Others have more flender horns, either fimple, or, as in the Blatra orientalis, articulated. Thefe horns are of various ufe, for to fome infects as the Gryllus campestris, they give intelligence when any thing approaches them from behind, to others they the organs of attachment to folid bodies, to others of progreffive motion. The extremity of the abdomen is likewife the fituation of the ting in thofe infects which poffefs it; fome have one, others two, which ferve as weapons of offence or defence. Some, as the Earwig, inftead of a fting have a fort of pincers or forceps at the tail, with which they defend themselves, and feize their prey. Laftly fome like the caterpillar of the Phalana Vinula, have two tentacula, like a two-pronged fork.

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I now come to the parts of generation in infects, which cannot be paffed over in filence. These are generally

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