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hi the discourse he made at the Areopagus, likewife places respiration among the best gifts of the Deity: " he &iveth to all life, and breath and all things."———Acts xvii. Z5. An action so necessary, and which is at the fame time common to all animals, requires that I should stop a moment to consider it, and endeavour to display all the skill and the wisdom os him who is its author.
Some antient philosphers, supposing that insects had neither wind-pipe nor lungs, have denied their respiration; but the air pump, invented by Otto Gerickin , and various experiments have convinced the moderns of the contrary. It we put an insect under the receiver of that instrument and then pump out the air, it first grows weak ami then dies. It is not therefore to be doubted but that insects like other animals, have both wind-pipe and lungs. The first gives a free passage to the air and the last like a bellows inhale it when they dilate, and expell it when they contract. If we stop the wind-pipe of animal9 they can no longer breathe and they die: the fame thing happens to insects when their respiration is obstructed. All insects have not the wind-pipe in the fame place of the body. In some it is found at the mouth, others in the extremity of their body toward the tail, in which they differ from all other animals.
All sorts of air are not proper for respiration; it must be temperate; air either too thick or too thin would destroy life; the one makes animals die in a very short time, and a too long abode in the other does not fail to produce the fame effect. But however necessary air may be for life, some there are which can dispense with it for four and twenty hours. If at the end of this period air is restored to them
they they recover their strength and do not appear to have1 been incommoded.
But what deserves our particular attention is, that these minute creatures, though air is so necessary to them fin summer, live during the winter with very little respiration if| any at all. They are ihen In a sort of sleep or lethargy, in a state between lise and death. The salt and the viscid humour which transpire from their bodies grow hard by the cold, and form a species of crust around them. In this state the pores of their bodies are contracted and in a manner shut: the vital spirits are concentrated in the interior parts of the insect, and they lose nothing of them by transpiration. As they make no motion^ nothing is dissipated: they remain always in the fame state, and have no occasion to respire in order to acquire new strength;
We cannot sufficiently admire the goodness of the Creator in providing for the wants Of his creatures; If air is necessary for their existence, he gives it to" them. The quality and quantity of this cannot be the fame for all animals ; he gives to each the organs necessary for inhaling just what is sufficient for them, and the kind that suits them. He weighs and destributes it to them as it were by measure. Men enjoy this precious gift in the fame way with insects; but how sew are there who have given themselves the trouble of reflecting on a benesit without which it would be impossible to live. How hive they reqifited Him for it? From our birth we have breathed, the air is common to all animals, and they enjoy it without labour or expencc ; and therefore instead of being gratesul, men become insensible to so precious & gift. As each inspiration and each expiration are so many authehtic testimonies of the power, of the wisdom and the goodness of God, there is not a
moment moment of our lives which does not invite us to celebrate his perfections and to express our own gratitude, lhe Pialinilt was penetrated with the justice of this reflection. "Let every thing that hatlj breath f fays he, praise the Lord." £salm Cl. 6.
"WHrN a living creature produces another of the fame species with itself, we say that it has engendered it. All generation is preceded by an intercourse between the male and the female. This is a general rule from which insects are not excepted ; the only difference to be remarked with regard to them is, that the way in which the male insects couple with the females is different in different species. However, this commerce fecundates the female and puts her in a condition to lay her eggs when the season has arrived. The Ephemera is singular in this point ; for it is only after the female has deposited her eggs on the surface os the water that the male fecundates them.
The variety among the eggs of insects is incredible : it may be said to equal the number of specie?. Wirhout considering the difference in their size, I mall only remark the most striking diversities among them whether from their figure or colours. The most common figures are the round, the oval, and the conic; but it must be attended to that there are some more and some less fe, and that some approach more to these figures than others. As to colours the dif
H fere nee serence is more striking. Some like those of some spiders have the splendor of little pe;:rls ; others like those of the silk-wcrm are yellow and of the a lour of a grain of millet. Others are of the colour of sulphur, of gold, or of wood. Lastly there are some green and brown, and among these last there arc various tinges of brown, such as yellow ish brown, reddish brown, chesnut, &c.
The matter which these eggs contain is at sirst a liquid substance, and asterwards forms the insect, which is very artfully enclosed in the shell. There it remains till the superabundant humidity is dissipated, and its members have acquired strength enough to break the egg, when it comes out. At this period it makes a hole in the shell raises up the little broken pieces, stretches forward thehead, which hitherto had been bent in towards the beliy ; displays its antennae, and puts them in motion-, brings out its legs one pair alter another, attaching itself with the sirst pair to the egj;, till the whole body is drawn out.
All insects do not remain equally long in the egg. A sew hours is sufsicient for some, while it requires many days, and even many months before othera break their prison. Eggs, which during winrer have been in a warm place, soon lose their humidity and are hatched prematurely. It is worthy of remark, and must not be forgotten, that those caterpillars which live on green vegetables, never leave their eggs till the herbs and leaves they seed on are sufficiently advanced. Providence has been careful to provide for their necessities, .ind to insure them of food the moment they want it.
Another circumstance not less remarkable, is that many of these eggs, notwithstanding their minuteness and delicacy are able to resist both cold and wet which do not destroy them. But even though numfeers of them mould be destroyed, that loss wduld be easily repaired by the sertility of the semales. One insect generally lays a great number of eggs; from thirty to sixty and.even some hundreds. This I learnt by the following circumstance. On the 6th of June i736, a forester brought me a butterfly, the upper -wings of which'were dark, spotted with eight white spots, and the under wings orange coloured. I sixed, it with a pin to a board, and on the afternoon of the fame day, found that it had laid four hundred and thirty one eggs of the size of a grain of millet, which resembled small pearls. At sirst they were soft, as I easily perceived because they were flat on that side which rested on the board, and resembled the top of a loaf. Their sigure cannot be observed while they lie one upon another; they must be detached to have a distinct view of them. In ten minutes they became so hard that when they were pierced with a pin they cracked like the shell of a pullet's egg. The liquor that issued from them was whitish like water. When put into the microscope, they appeared semi-transparent like a hog's bladder. The next day the fame butterfly had laid 170 e^s making in all six hundred and one.
The observation I have just made to shew the sertility of insects will likewise prove that eggs are soft when discharged by the semale; this I was convinced of likewise by another experiment. I took a butterfly of another species which I sixed to a board like the other. As loon as it had laid an, egg I touched it with the point of a pin, and found that I could make little pits in it,nearly as in a bladder which is not quite blown. Some :':nutes asterwards these eggs became hard, and when 1 pressed them strongly, they broke in several places like the eggs of a pullet.'
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