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tion. A famous Chemist, a man worthy of credit, has at least affured me that they may be reduced to the state of water. I think myself therefore ftill the more intitled to conclude that all bodies without exception are compofed of the fame matter and are derived from the fame origin.

The distance between the two kingdoms is fo very indistinct that it is difficult to fay where the one ends and the other begins. We fee for instance that corals are the limits between the mineral and the vegetable kingdoms. They are minerals in matter and hardnefs, vegetables in their manner of growth; and this has made them be claffed as marine plants. The paffage from vegetables to animals is not lefs abrupt. Here we find the Zoophytes which the old Botanifts fupposed to be as much related to animals as to plants. Here also we find Infects which in many circumstances approach to the nature of vegetables but which in others fo nearly resemble animals that it is impoffible to deny them a place in that kingdom.

On examining infects we find that they are not furnished with bones like other animals, nor indeed have they any occafion for fuch. Let large and heavy bodies enjoy thefe for the purpose of supporting their mafs of flefh, and of preventing them from finking under their burthen. But to light and small bodies like thofe of infects, whofe fubftance properly speaking is not flesh, and which fupport themfelves fufficiently, bones would be of no ufe. It is likewife peculiar to infects to be destitute of blood. That which is feen on killing a flea or a bug, is only what they have pillaged from fome other animal. They have however a fort of lymph, which performs to them the fame animal functions which the blood does to others.

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If we compare infects with the greater animals; they will appear extremely fmall. Man, the hydra, the crocodile, the whale, the eagle, and the elephant; are millions of times larger than many infects. When likewife we compare infects among themfelves, how different are they in this refpect from one another? How minute is the fly Serapico, and that which lives on meal, and which we can hardly difcern without the aid of the microfcope? How minute must not that worm be which is found in vinegar, when according to Mr Leewenhoeck myriads of them are found in a fingle drop of that liquor! How many times must not a mite, which to our eyes appears no larger than a point, exceed those minute animalcules! And how diminutive does not a mite in its turn appear when compared with the larger infects. It is this comparifon, which has obtained for fome of them the title Great, which they would not have merited had they been opposed to the animals of large fize. It is accordingly in a relative fenfe that we muft underftand the term, when we apply it to a fpecies of East India Scorpions, which are nearly a foot long; or to a fort of fpiders of the fame country, nearly as large as one's fift. These large infects would them. felves be very finall, when compared to an ox or a camel.

The fkin of infects is different from that of other animals. It pretty much refembles parchment, but varies a good deal, in the different fpecies. In fome it is tender, in others hard. In the crab it is a fort of enveloping cruft. In the oyfter a fhell in which the animal is enclofed. Some are covered with fcales like fishes, others with feathers like birds. Some have a thick and coriaceous fkin, others have it fimooth, like the human; while others have it rough, like thofe of quadrupeds. Their body is compofed of feveral rings which are fo many differ

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ent incifures, more or lefs deep, and often much more fo than thofe of the ferpent or lobster.

They have not exactly the fame number of members which the other animals are furnished with. The legs are wanting to fome, the wings to o thers; perhaps they may have fomething lefs alfo, or fomething more in their vifcera; but from thence it does not follow that their bodies are imperfect as fome philofophers have imagined. An animal is confidered to be perfect when it is furnifhed with all the parts that are neceffary for its fubfifting in the state appointed for it. The privation of those which are abfolutely neceffary to another fpecies is no proof of imperfection. A houfe built according to the rules of architecture, would never be confidered as an imperfect edifice, because it had not fo many apartments as a palace. The perfection of a compound does not confift in the abundance of its parts, but folely in their proportion and aptitude for the functions they are deftined to perform. Each infect is therefore as perfect in its fpecies as the other animals in theirs; and it would be as abfurd to deny them this quality as it would be extravagant to maintain that man is not perfect without wings, the horfe without fins, or fifhes without feet.

Thefe pretended defects, and their diminutive fize have made infects be regarded with contempt; but the enlightned naturalift confiders them in a very different light. Every Infect however fmall it may be, is furnished with all the parts that are neceflary for it. As no one of them can be taken from it without maining it, fo no one could be added without furcharging it with an ufelefs load; in this its perfection confifts. I will not fay with St Augufline that the foul of a fly is as perfect as the

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fun when it is most brilliant; but I would willingly afk, with that father, what are the fprings that put in motion limbs fo delicate, which transport thofe fmall bodies from one place to another to fupply their neceffities and which urge and direct their feet or extend and agitate their wings when they run or fly? agree with him that there are many things marvellous in thefe functions; but I find ftill more in the minutenefs of the creatures which perform them. If therefore I were to appretiate the foul of an infect, that confideration would appear to me at leaft as proper for exalting its excellence as the other. Indeed, how wonderful is it to behold organized inachines moving and acting, fifty of which put together would not make the volume of a grain of fand! How delightful would it not be could we perceive thofe parts the delicacy of which is fo great that they are invifible to our fenfes! When we confider all this, what can we think or what can we fay, but that God is admirable in all his works, and that the Itructure of these little animals which creep on the earth, furnishes us with as abundant matter for adoring the power, the wisdom and goodness of the Creator, as the ftars which traverse the wide extent of Heaven!

CHA P. III.

OF THE DIVISION OF INSECTS.

IN confidering infects with regard to their external form only, they may be conveniently comprehended in two general claffes. The first will include those which have not feet, and the fecond those which have. Infects of this laft clafs, may be fubdivided into two different orders. The one have wings, the other want them; and as all those with wings do not resemble one another, hence arifes a new fubdivifion. Some have the wings quite naked, while nature in order to preferve those of others hath covered them with a cafe. There is befides ftill another diftinction to be made among those with uncovered wings; for in fome they are perfectly fmooth and tranfparent, in others they are mealy. In these last the cover is fometimes only partial.

In order to avoid confufion it will be proper never to give the general name of worm but to thofe infects which are deftitute of feet, excluding every other to which the word is generally applied. However this may be, we must enumerate among the infects without feet, the three fpecies of leeches which are known; that of rivers, of ftagnant waters and of the fea. To them must be added the Gordius,

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