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At sirst nothing is seen but an aqueous mafte?,- it little time however discovers in the middle, a darkpoint which afterwards becomes the insect. In this it is entirely enclosed, but it cannot be perceived without the aid of a gooJ mkroscope. Under the hard shell of the egg is found a pellicle, sine and delicate, in which the insect is wrapt up as in a matrix. It is there rolled up with so much art, that notwithstanding the smallness of its apartment it has abundance of room, and is furnished with all the members it ought to have. When we view the surprising compastnes* Sfnd disposition of the whole, we cannot sufficiently admire the wisdom of him who has consined so much matter in so little space. The insect as I have already (aid remains in this state till having become larger it acquires strength sufsicient to burst itsprison walls and to come forth;
The little care which insects rake of their eggs deserves the reader's attention. After having deposited them, they leave them, and go away without any further concern; they resign the labour of hatching them to the nature of the place where they are laid, and to the heat of the sun. fn due time the caterpillars issue from the eg£S without any desence against the injuries of the air. By this they are distinguished from the rest of all other animals. A woman nourishes and protects the child in her womb for nine months; the semales of quadrupeds do the fame with their young; birds lay their egjis in nests, and hatch them with the most diligent and painsul incubation.Fishes alone in this respect resemble insects; they ky their spawn upon the shore without any other precaution than that of chusing a place they think the most proper for depositing it in; they then abandon it, and the young are brought forth without t!ie assistance of their parents.
As insects produce such a number of eggs it is easy to conceive that there must be a proportionable number of the animals themselves. It is no doubt for this reason that the Scriptures compare numerous armies to insects. The author of the Book of Judges ia order to give an idea of the multitude of Midianites^ and Amalekites, fays, that " they came with their "cattle as grasshoppers for multitude, and they en
"tered into the land to destroy it." Judges vi. 5.
The Prophet Jeremiah makes the fame companion in speaking of the troops which Nebuchadnczar was to bring into Egypt. "They shall come against her "with axes, as hewers of wood. They shall cut "down her forest, faith the Lord, though it cannot *' be searched, because they are more than the grasshop"pers, and are innumerable." Cap.- Xlvi. 22,25. The miseries that were to afllict Nineveh the great, are represented by Nahum under emblems drawn from insects. 'Make thyself many, says that Pro'phet, as the canker-worm, make thyself many as
* the locusts. Thou hast multiplied thy merchants, 'above the stars of Heaven; the canker-worm spoi'leth and flieth away. Thy crowned are as the lo
* custs, and thy captains as the great grasshoppers,
* which camp in the hedges in the cold day, but
* when the sun ariseth they flee away, and then place
* is not known.' Chap. m. 15,16,17.
One thing which contributes greatly to the prodigious multiplication of insects is the little time they require from their exclusion by the parent semale to their being capable of laying eggs themselves. This is so rapid as to have given occasion to a vulgar saying that the louse may be in four and twenty hours a mother, a grand-mother and a great grand mother. We must not therefore be surprised that insects multiply so remarkably, and that such pains are requisite to destroy them.'
What I have said in this Chapter anight furnish abundant matter for reflection. It is allowed that insects are destitute of reason; the •wisdom theresore of their conduct, the justness of their precautions, and in a word every thing they do which is agreeable to reason, does not proceed from themselves. From whom then do they derive it? Who hath taught them the season and the manner of propagating theit species? Who hath directed them to lye wiih such compactness in their eggs without being in the least uneasy ? How do they know the precise moment when it is proper to issue from their eggs? Who hath prescribed to each species the number of eggs it is to lay? Who hath endowed them with the power of resisting the inclemencies of the weather and of coming forth without incubation? One must be wilsully blind not to acknowledge in these traces the hand of an all powersul Being whose wisdom is unsearchable. Who' but he could have made them capable of so many different functions, and have endowed them with instinct to perform them? A great number of eggs of insects perish, and animals devour another parr. Had not providence supplyed the loss by the promptitude with .which they encrease and their great sertility, the various species would have been in danger of perishing, or at least would not have been produced in sufficient quantities to seed the other animals' that depend on them.
THE subject I am to treat of in this Chapter is sq singular, that it is peculiar to insects alone ; and as there is nothing resembling it among the other animals, it deserves our particular notice ; and the rather because if we are not attentive to the tiansformations of insects, and do not know exactly all the forms which the fame individual successively assumes, we shall be in danger of making two or more insects pf one and the fame animal.
It is not the actual substance of the infect which undergoes a transformation j it is merely the external form which is changed. The parts it is composed of, after its metamorphosis, are enveloped and masked as it were under different fains, from which the animal disengages itself, successively, as it grows in bulk, and at last appears with all the members necessary for it in its last state. When the period of transformation arrives we often fee caterpillars quiting the leaves and plants they have hitherto fed on, and transporting themselves to a more commodious place. Some however do not abandon their first situation, but attach themselves to the stems or branches of the plant which has formerly afforded them protection and support. Then as if loathing the food they had at first greedily devoured, they cease altoge* ther to eat. So strict a fast is undoubtedly necessary to prepare them for the change they are about to undergo: and this seems the more probable as they discharge all the fæces their intestines are silled with, before they attempt the change.
The metamorphoses of all insects do not resemble one another, but are generally divided into four different, classes. The sirst comprehends those insects which aster being; formed in their egg, without the aid of food, and which after having taken, by the evaporation of the superabundant humidity, the necessary consistence, quit that state and issue from the shell under the form they are to retain during lise, without undergoing any other transformation. To this class belong spiders, lice, fleas, the onisci, the luli, &c. The transformation of the second class consists in this, that the insect which was enclosed under a disguised form in an egg, and without food, after having been fortisied by the evaporation of the superabundant humours, leaves the shell and appears under the form of an Insect without wings with all its other appropriate members; which in this state eats and grows till having entred a second time into what is called the Nymph state, it issues from that state with wings and is capable of propagating jts species. I h> elude in this division, ants, dragon slies, grasshoppers crickets, the mole-cricket, cimices, aquatic flies, &c. In the third transformation, the animal, after having issued from the egg where it also lay in a disguised ihape, and without food, appears under that of an insect which eats and grows, while the members of the animal into which it is to change, are formed ttnder its skin, which it at last quits, and becomes a nymph or chrysalis; and then aster the evaporation of the superfluous humidity, is transformed into its last state, which is that of a persect insect. This class includes bees of all foits, gnats, beetles, butterflies,