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If we compare insects with the greater ani tnals; they will appear extremely small. Man, the hydra, the crocodile, the whale, the eagb, and the elephantj are millions of times larger than many insects. When likewise we compare insects among themselves, how disserent are they in this respect from one another? How minute is the fly Serapico, and that which lives on meal, and which we can hardlv discern without the "aid of the microscope? How minute must not that worm be which is found in vinegar, whert accofding to Mr Leewenhsteck myriads of them are found in a single drop of that liquor! How many times must not a mite, w^ich to our eyes appears no larger thart a point, exceed those minute animalcules! And how diminutive does not a mite in its turn appear whert compared with the larger insects. It is this comparison, which has obtained for some of them the title Great, which they would slot have merited had they been opposed to the animals of large size. It is accordingly in a relative sense that we must understand the term, when we apply it to a species of East India Scorpions, which are nearly a foot long; or to a sort of spiders of the fame country, neatly as large as one's sist. These large insects would themfelves be very small, when compared to an ox or a camel.
The skirt of insects is disferent from that of other animals. It pretty much resembles parchment, but varies a good deal, in the difserent species. In some it is tender, in others hard. In the crab it is a sort of enveloping crust. In the oyster a shell in which the animal is enclosed. Some are covered with scales like sishes, others with seathers like birds. Some have a thick and coriaceous skin, others have it smooth, like the human; while others have it rough, like those of quadrupeds. Their body is composed of several rings which are so many difserent etit incisuYes, more or less deep, and often much moire so than those of the serpent or lobster.
They have not exactly the. same number of members which the ether animals are surnished with,; The legs are wanting to some, the wings to cithers; perhaps they may' have something less also, or something more in their viscera; but from thence it does not. follow that their bodies are impersect as some philosophers have imagined. Art animal is considered to be persect when it \s famished with all the parts that are necessary for its subsisting in the state appointed for it. The privation 6f those which are absolutely necessary to another species is no proof of impersection. A house built according to the rules of architecture, would i,cvet be considered as an impersect edisice, because it had; hot so many apartments as a palace. The persection of a compound does not consist in the abundance of its parts, but solely in their proportion and latitude for the sunctions they are destined !6 perform. Each insect is therefore as persect in its specie as the other animals in theirs; and it would be as absurd to deny them this quality as it would be extravagant to maintain that man is not persect without wings, the hoise without sins, or sishes without ftec.
These pretended defects, and their diminutive size have made insects be regarded with contempt J but the enlightned naturalist considers them in' a very different light. Every Insect however small it may be, is surnished with all the parts that are necessary sor it. As no one of them can be taken from it without maiming it, so no one could be r.dded without surcharging it with an useless load in this its persection consists. I will not fay with St Augustine that the soul of a fly is as persect as the. lun when it is most brilliant; but I would willingly ask, with that father, what are the springs that put in motion limbs so delicate, which transport those small bodies from one place to another to supply their necessities and which urge and direct their seet or extend and agitate their wings when they run or fly? 1 atrree with him thaf there are many things marvellous in these functions; but I sind still more in the minuteness of the creatures which perform them. If therefore I were to appretiate the foul of an insect, that consideration would appear to me at least as proper for exalting its excellence as the other. Indeed, how wondersul is it to behold organized machines moving and acting, sifty of which put' together would not make the volume of a grain of sand! How delightful would it not be could we perceive those parts the delicacy of which is so great that they are invisible to our senses! When we consider all' this, what can we think or what can we fay, but that God is admirable in all his works, and that the structure of these, little animals which creep on the earth, surnishes us with as abundant matter for adoring the power, the wisdom and goodness of the Creator, as the stars which traverse the .wide extent of Heaven!
Of ^he Division Of Insects.
In considering insects with regard to their external form only, they may be conveniently comprehended in two general classes. The sirst will include those which have not feet, and the second those which have. Insects of this last class may be subdivided into twodifferent orders. The one have wings, theother want them; and as all those with wings do not resemble one another, hence arises a new subdivision. Some have the wings quite naked, while nature in order to preserve those of others hath covered them with a case. There is besides still another distinction to be made among those with uncovered wings; for in some they are persectly smooth and transparent, in others they are mealy. In these last the cover is sometimes only partial.
In order to avoid confusion it will be proper never to give the general name of worm but to- those insects which are destitute of feet, excluding every other to which the word is generally applied. However this may be, we must enumerate among the insects without seet, the three species of leeches which 2ie known; that of rivers, of stagnant waters and of the sea. To them must be added the Gordius, F % . which jyhjch the Germans called the thread-worm, because jt is hardly thicker than a thread. The water Tipulæ, jhe jarvæ of the small v/ater Tipulæ, which when united jn great numbers, form on the surface of the water a kind of green carpet; and a water wormf whose mouth resembles the opening of a trumpet. In water is also found the insect called the Hippocampus, Sea-worms, and Sea-stars, and two worm^ one of which has a large, and the other a small proboscis. Ewth worms are not in less quantity. Besides the common earth worms, there are some tq be found in dunghills, in grafs, in corn, in pulse, in roots, in wood, and even in the medulla of putrid wood. Many species are found in'the leaves of plants. Some six themselves on the upper, some on the under surface, in order to conceal themselves; some lodge in the substance of the leaves, others in their galls. Some penetrate the fruit of trees, others enter into bee-hives. Some attach themselves' to animals, like those which are found on beetles, and which adhere to sishes, to birds, to dogs, and swine, and other beasts. Everi ^he intestines of animals are not secure from them; some are found in the entrails of silhes, of horsesj and of men. Those found in man are nqt all of the same species, some are round and long, others round and short. Some are long and depressed, some short and depressed; and some are bred iii wounds and putrid sores. ''
Insects with seet, and without wings are very numerous, and have not all the fame number of seet. I know a species of water flea, which has only two. The species which have six are most numerous; among these is comprehended the Asilus or Oellrum Marinum, the Corculus, water bugs, land fleas, a fort of mites, which breed in the parenchyma of leaves, certain worms found in stones, the ajelli arvenses, the aphides of leaves, the Cochineal