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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 thofe minute animalcules! And how diminutive does not a mite in its turn appear when compared with the larger infects. It is this compari fon, 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 must underftand the term, when we apply it to a species 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 themselves be very small, 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 oyster 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 fmooth, like the human; while others have it rough, like thofe of quadrupeds. Their body is compofed of feveral rings which are fo which are fo many differ

ent

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 mem bers which the other animals are furnished with. The legs are wanting to fome, the wings to 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 fub fifting in the ftate 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 antitude. for the functions they are de'tined to perform. Each infect is therefore as perfect in its fpecie 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 conficers them in a very different light. Every Infect however fmall it may be, is furnished with all the parts that are neceffary for it. As no one of them can be taken from it without maiming 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 moft brilliant; but I would willingly afk, with that father, what are the springs that put in motion limbs fo delicate, which tranfport 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? I agree with him that there are many things marvellous in these functions; but I find ftill more in the minuteness 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 machines 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 say, but that God is admirable in all his works, and that the structure of these little animals which creep on the earth, furnishes us with as abundant matter for adoring the power, the wifdom and goodnefs 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 firft 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 thofe with wings do not refemble one another, hence arifes a new fubdivifion. Some have the wings quite naked, while nature in order to preferve thofe of others hath covered them with a cafe. There is befides ftill another diftinction to be made among thofe with uncovered wings; for in fome they are perfectly smooth and transparent, 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 muft enumerate among the infects without feet, the three fpecies of leeches which are known; that of rivers, of flagnant waters and of the fea. To them must be added the Gordius,

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which the Germans called the thread-worm, becaufe it is hardly thicker than a thread. The water Tipula, the larvæ of the fmall water Tipula, which when united in great numbers, form on the furface of the water a kind of green carpet; and a water worm, whofe mouth refembles the opening of a trumpet. In water is alfo found the infect called the Hippocampus, Sea-worms, and Sea-ftars, and two worms one of which has a large, and the other a finall probofcis. Earth worms are not in lefs quantity. Befides the common earth worms, there are fome to be found in dunghills, in grafs, in corn, in pulfe, in roots, in wood, and even in the medulla of putrid wood. Many fpecies are found in the leaves of plants. Some fix themfelves on the upper, fome on the under furface, in order to conceal themselves; fome lodge in the substance of the leaves, others in their galls. Some penetrate the fruit of trees, others enter into bee-hives. Some attach themfelves to animals, like thofe which are found on beetles, and which adhere to fifhes, to birds, to dogs, and fwine, and other beafts. Even the intestines of animals are not fecure from them; fome are found in the entrails of fithes, of horfes, and of men. Thofe found in man are not all of the fame fpecies, fome are round and long, others round and fhort. Some are long and depreffed, fome fhort and depreffed; and fome are bred in wounds and putrid fores. :

Infects with feet, and without wings are very numerous, and have not all the fame number of feet. I know a fpecies of water flea, which has only two. The fpecies which have fix are most numerous; among thefe is comprehended the Afilus or Oellrum Marinum, the Corculus, water bugs, land fleas, a fort of mites, which breed in the parenchyma of leaves, certain worms found in ftones, the afelli arvenfes, the aphides of leaves, the Cochineal

Worm

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