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sufficient for animating a body compleat in its parts and sunctions : for when we examine these two sorts of animals,we see evidently that each is a single insect, not a concatenation of insects united end to end, as some people aver of the Solitaire; and thus I do not conceive what can be alledged against the conclusions which result from the facts we have detailed.
InseEls have an artery. This is the vessel which it is supsupposed forms the heart of insects; or if you will, it is a string of hearts running through the whole length of their back. In caterpillars the pulsations begin in it at the posterior extremity, and go successively from articulation to articulation towards the head. M. Reaumur on the subject of these pulsations mentions a very singular fact. He fays that we may observe in chrysalids newly transformed, and still transparent, that these pulsations change their direction, and that the great artery which, in the caterpillar, push the fluid from below towards the head, pulh it in the chrysalis from the head towards the tail, a circumstance which supposes that in these two states the circulation of the fluid which serves the purposes of blood proceeds in a quite contrary direction. I regret that I have hitherto neglected to repeat the experiment on chrysalids newly transformed ; for although I do not doubt that the fact is so in the caterpillars which that illustrious author had examined, I have reason to believe that either that new motion does not continue for any long time, or that it is not common to all chrysalids. For having found a species of caterpillar which surnished me with, what is very rare, a chrysalis exceedingly transparent, and through which I could see distinctly all the movements of the artery, I took some of them a sew days after their transformation, and set myself to examine tlysm at different times with the greatest possible attention, and that during the space of several months, that their transparency lasted ; and I always observed in them, with the greatest certainty, that the pulsations of their heart, or if you will, of their great artery, had in no degree changed their direction in the chrysalis; but that they continued during all that time to proceed from the tail towards the head, as they had formerly done in the caterpillar.
Page 168,1. 23. * Some are sound to ruminate. Such are the sour species of locusts mentioned in Leviticus, Ch. Xi, 21 and 22. "Yet these may ye eat of every flying creeping thing that goeth upon ail four, which have legs above their seet to leap withal upon the earth. Even those of them you may eat; the locust after his kind, and the bald-locust after his kind, and the beetle after his kind, and the grasshopper after his kind."
I am not sure that there arc any insects which ruminate. This is a circumstance which Swammerdam supposes of the grasshoppers, and which Mr Lester thinks be can prove from Scripture: but in my opinion, the passage proves no such thing. The animals are there distinguished into four classes, viz. Quadrupeds, or as the Hebrew text expresses it Beasts, (taking this word in a more extended sense than is generally given to it,) sishes, birds and reptiles or insects. The sovereign legislator indicates, with regard to the two sirst classes, the characters by which the animals permitted by the law to be eaten were to be known. Those of the sirst were to be ruminating animals, to have the hoof divided, 'and the foot cloven. Those of the second class were to have scales and sins. As to the third, the cl;an beasts are not diitinguistied from the unclean by any character; but instead of this, the law expressly mentions those birds which were not to be -eaten. And as to the fourth class, the law contents itself with forbidding to cat, " every flying thing that goeth upon all-four, having, belides its seet, legs to leap withal;'' and it excepts from this general rule only the four forts of locusts mentioned in the note above. This at least is the sense I would give to this last passage, which is also countenanced by the Hebrew text; for the version of those interpreters is hardly admissible who translate it, some thus," Yet these may ye eat of every flying creeping thing that goeth upon all four, which have legs above their seet to leap withal f" and others according to the observation of M. de feesser himlelf, ' which goeth upon four seet, and which have not legs to leap withall,' But whatever interpretation may be given to the place sited, I do not know how it can follow that the four species of locusts, there allowed to be eaten, were among the number of ruminating animals, or that the bare mention as their four seet, is sussicient to make them be considered as subjected to the law est .bhihed before in the same, chapter, for animals of the first class, or to infer from the passage that because the law allowed the eating of these locusts that therefore they n.ust ruminate, which seems to me to be the reasoning of our author.
Page 169,1. 8. Jr formtd es little vesicles. If we are to understand here by lung', a ipongy substance filled with small vesicles, and penetrated in every part by the different vessels which in the inspiration of the larger animals, receive the air by means of the trachea, I doubt much if any such lungs have hitherto been discovered in any insect, and the two vesicles in bees which the author seems to consider as lungs on the authority of Swammerdam are by no means such. The bronchia;, of which a great number are found dispersed over the whole body in most insects, seem to serve them instead of lungs, and to supply the want of that spongy substance, which hat never yet been detected in them.
In inse&s it is nothing but skin. "We find, it is true, in the bodies of insects a number of vessels which seem to be composed only of a single membrane; but these arc not the pulmonary vessels j which as we have said elsewhere are tubes, constantly open, surrounded with a thread closely wound round them, like the slender wire round the base string of a violin. That thread is easily disengaged from these trachex, by passing lightly over them a moistened pencil. Those vessels make a very curious object in the microscope; we are struck with admiration at seeing those branches, which for the most part are incomparably more slender than a hair, and of which there are thousands in the body of a single insect, fabricated with so much art.
Page 169, L 39.
Those of others have five furrows. It is very general with those caterpillars which have a horn on the posterior part, to void those channelled fæces ; the furrows are likewise often crossed by intersections which divide these fæces as it were into different rings. The cause of their regular and uncommon form certainly deserves investigation; it seems rather to depend on the muscles of the anus, than on the internal figure of the rectum, which does not seem to be
a « Vessel of sufficient firmness to give such a form to excrement so hard as theirs.
Page 174.1. 1©.
An ant as big us a middle [zed d#g. We would have been very much obliged to M. tie Bulbequius if he had been so kind as to fend some of those monstrous ants to Europe. He would have then had the pleasure us delivering natural-' ists from the repugnance they mull feel in believing lo extravagant a fact.
Page 174, 1 15.
Without the aJJiJJance of a micro/cope. This is not all. There are some which the most excellent microscopes can hardly make visible, as we have already remarked. Page 175,1. 8.
Shine Hie turning «a/s.---Beiides the infect"! which shin: in the night, such as the glo>v worm, &c. thcic is one found in Surinam which deserves to be known on account of its Angularity. According to the description which Mad. Merian gives of it, this anim-d, in its creeping state, seems to have a form approaching: **v»t of cur la»..ii grj&ioppcrt, but is much larger*, like them it has a long proboscis by which it fucks the juice from the flowers of the pomegranate, and this proboscis remains with it all its life. After having quitted one (kin, it changes its form, and appears under that of a large green fly like our Cicada. Its flight is then very rapid, and the noise it mtkes with its wings is like the found of a cymbal. Although according to the ordinary course of nature, an insect, after having acquired wings, undergoes no farther change,yet this one, by the concurring testimony of the Indians which Mad. Merian fays she had in part verified by her own experience, Undergoes ltill a last transformation which renders it luminous, and which then procures it the name of the lantern fly. (Fulgora Laternavia Lin.) In this last transformation, besides other inconsiderderable changes which happen to :ts body and wings, thereissues, from the forepart of it« head, a very long transparent bladder, coloured with redd.sh and greenilh streaks, and which diffuses a light lufficient to enable a person to read pretty small print. This animal, by the description die gives of it, is then about four inches long, and the bladder occupies about a fourth of its whole length. Before
3 F 2 Mad.
Mad. Merian was acquainted with the luminous quality cf this insect, the Indians brought her many of them whici she shut up in a large box. Being alarmed one night with a singular noise which she heard in the house, she got up, lighted a candle, and went to see what it was. The noise came from the box; she opened it, and immediately there issued a slime, which encreased her emotion, and made her throw down the box, whence there was now dispersed a new beam of light, as each animal got out of it. We may believe her sear did not long continue, but soon gave place to admiration, and she immediately set herself to regain animals so extraordinary, which had taken advantage of the sesr they had occasioned to make their escape. <
Page I 76, 1. first.
.fiy the clapping of the wings again/} one another. A great number of insects make a buzzing with their wings by agitating them without sufsering them to touch each other, or even to strike their body. Such are all the flies with two wings which make a noise in Hying, and among others the gnats. In this case the found they excite is formed probably either in the fame way with the sound made by a stringed instrument, merely by their vibrations; or it is made by reiterated strokes made on the small scales which some flies have under their wings; or perhaps by the extremely rapid agitation of those two small moveable poiser? which the wings of that sort of sties have near their Origin. These wings striking against the poisers when agitated mny cause this noise, by an efsect similar t» the sound produced by a cord in vibration, when it meets with any body which touches it without resting on it. An easy experiment may perhaps elucidate the matter; we have only to cut away tloore small poisers and scales from the large buzzing sties which have them: if, after that operation, they continue still to buzz when they fly, it will be a proof, that the noise proceeds from the mere agitation of the wings. But if, on the contrary, the buzzing ceases, we may then with reason inser, that the poisers and scales concur in producing the noise. For there is little probability that it i* formed by them alone; the vibrations of bodies, lo short and so del'cate, do not appear capable of producing tones so grave; although it is act, however, iumcitible j confute]ing,