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Pace 86, L 18.
* Whom their cruel country had expelled. The Instance Here adduced by the author is striking, because it is later than some others, and has happened iu our days-. But if we go back to the last century, and reflect on the vast multitudes of Protestants who were banished from France their native country; who were at first destitute of every thing, but who soon found a retreat in Germany, in England, in the United Provinces and in Switzerland, we shall be convinced that Providence did not abandon them any more than the people of Salzburg. The greater part of the French found themselves in a short time in a situation infinitely more agreeable' than that which they had left. This fact is so true, that numbers would have refused to quit their new establishment, though they had been permitted to return to their native country. Thus God accomplished ia them the promise he made to those who should leave father, mother, wife, children, &c. for his fake. He repaid them an hundred fold. Note of the French Translator.
Page 87,1. 11.
J9 fort of moving house. If there be animals, which after having got entrance into our bodies with our food, increase there and multiply, it is probable that their number cannot be great, considering that an animal brought to life in a temperate air, and accustomed to a certain kind of food, ap^ pears little fit to endure the heat of our stomach, the corrosion of the solvent humours which enter it, the humidity and moisture with which it is filled, the trituration and great diversity os the alimeuts which are there digested. All this seems likely to cause its death in a few instants; accordingly it is with difficulty I can believe that the worms which are so often found in our intestines have been introduced with our food; although it is very difficult to fay how they have gbt admittance otherwise, and tho* all that has been advanced on the subject hitherto is nothing but Conjecture, and that too sufficiently improbable.
Page 87,1. 29.
Ready to devour our bodies. The worms which commonly attack our dead bodies are not the fame which inhabit them when living. The origin of these last is unknown to its; but we know that the first are produced from fiies which.
lay lay their eggs on flesh, and other substances about to grow' putrid. Before the corruption of those substances they are not proper food for the larv.e of these fses, and accordingly they neVer deposit their egjs on living bedies: and it is sufficient to prevent a dead body from being eaten by worms, to desend it from flies. As to the worms which are found in our bodies while alive, it is probable that they die wkh us, and that our bodies when become cold and corrupted, are incapable of preserving the lise of animals accustomed to a great degree of heat an3 to fresh food. "What consirms this idea, is, that we see lice and other vermin which prey upon living bodies, abandon them when dead, and even when attacked by disease.
Page 88,1. 15.
The motion os snails is wry slow. The mechanism of their progressive motion is more curious than is generally imagined, at least if it resembles that of the large spotted snails which I have examined. When they are made to move in a glass, we see their under surface divided into three bands, which run from the head to the tail; the middle one alone seems to act; all the motion at that time observable in the other two is only that by which they apply themselves immediately to the bodies they pass over. The action of the middle band consists in a very obvious undulating motion, very Itgular and rapid, proceeding from the tall to the head, the undulations succeeding one another at equal distances, and so near, that twenty of them may be counted between the head and the extremity. The body of the a* nimal obeys but little the rapid motion of these undulations. It appeared to me, that during the time occupied by an undulation, in running the whole length, the animal itself proceeded only the space between one undulation and another. Its progressive motion is therefore twenty times flower thanthe undulatory motion, and it may be said that to advan.'e one step, it must make twenty. Who could imagine that this animal runs lo fast, whtn it proceeds so slowly!
Page 89,1. it<
The blind mole. Molce are by no means blind, but their eyes are not tormed to bear the light of broad dav. Thev are very small, and deep seated; they must be sought for to be seen. It was necessary that they should be chus hidden to
desend defend them from the falling in of the earth, in which this animal is continually digging. It is this wife precaution in nature, which makes people believe that mole:, are blind; they would become blind if they had less the appearance of being so.
Page 90, 1. 14.
To prevent their falling to the bottom. Aquatic infects are not confined to a lingle mode of progressive motion. Many walk, fw:m, and fly, others walk and lwim, and others possess only one of those means of motion. Of thole which, swim, the greater part swim on the belly, and fame on the back. Toswimthemore quickly, some have the power of filling themselves with water, and of ejecting it again torcibly by the posterior extremity; this pushes them forward with an effect stmiluto that which pushes back the Eolipile, or makes a rocket ascend. In this way thclarvæ of the LioellulaPuella swims. Others have the hind legs long, and made like oars which they use in the same way. Of those which walk, some go on the belly, others on the sides, and others fjn the head and the tail. Infects of this last fort have no feet, they have a fort of limb at each extremity of the body which serves them for feet, and by which they can attach themselves with inconceivable force to the bodies they want to hold by. Some species of this kind have the power of elongation and contraction, in a degree which exceeds imagination, and this makes them take huge sttides. Many aquatic infects properly speaking neither walk nor swim; bur by a progressive undulation of the under part of their body, they can produce the effect. There are even some that without the smallest observable external motion glide through the water in every direction and with great velocity. Many of these are Proteusts which change as it were their form at pleasure, and take such odd shapes that if one did not know them, one would never take them for animals,
Page 91,1. 3.
Like a bow after the arrow is let fy. "What facilitates (his elastic motion is their having hooks at their anterior part by which they connect themselves with the posterior part of their bodies. When they make an effort as if to rdiore themselves at the time that they are bent double,
these these hooks at once loose their hold, and cause those jerk« by which the animal leaps from place to place.
Page 92, 1. at.
Excepted from this general rule. In this example it is remarkable that the insect is a butterfly, and that butterslies in general have a very uneqnal mode of flight, much more so than moths. Perhaps the reason is that the four wings of the former are almost inflexible, and quite extended j while the latter, at least the greater part of them, can fold their wings like a fan; which may help to direct their flight.
Page 92, L 24.
The flight of the male being most rapid. There are even among butterflies and beetles some species where the semales do not fly at all, as has been already mentioned.
Page 96,1, a.
They a!l*dread the rigour of winter. The Winter how* ever is formidable but to sew species of insects. Besides that the greater part resist the most intense cold, and that a severe winter kills sewer than an open one, I have already said in another place that there are many kinds for which the season of frost is the season os eating and growing: there are many caterpillars of this kind. I am soprised to sind them mentioned by no author; probably because they have never thought of seeking for them in that severe season. Winter insects grow much more slowly than those of the Summer. They do not eat when the frost is very intense, but they immediately begin to seed when it grows more moderate. It is generally towards spring, that they transform themselves into nymphs or chryfalids.
Page 96, 1. 19.
Seen assembling in crowds. This relates only to certain species aceustomed to live in society. We do not sind insects that live solitary, and which are certainly the most numerous, assembling together to pass the winter.
Page 97, 1. 3.
* Dr Wclsch mentions a beautisul jasper which on one side had many deep and winding holes, visibly the work of
Certain Insects which had lived in them. Besides, a'certaifi yellowish dust in them indicated that they could only have been the holes of worms; and Barcbewitz fays that a species of white ants in the East Indies live on iron.
Page 63,1. 13.
San J, Jlones, iron. These substances appear so little fit to be food for infects, that one would need at least better proofs than those which the author has brought, to credit a fact of this nature.
When an insect works in the sand, a careless observer might easily b: deceived, and imagine when he sees the animal taking sand in its mouth that it is for the purpose of eating it, though in reality it is only for constructing its habitation.
A stone full of holes, dr which appears to have been attacked by some infect, is not a valid proof that that insect has □fed it as food. Some insects indeed build the cafes in which they live with fragments of stone and other hard substances. Is it not probable that if any insect had attacked the jasper which the author mentions in the above note* it must have been only to construct its abode with the fragments, or to form a lodge for itfeif in the stone? But it is not even'probable that infects ever lodged in that jasper, except they had done so before its compleat petrifaction. Nothing is more common than to find fishes, bones, shells and other animal substances in the heart of the hardest stones. But it must not be inferred from this, that those fillies, or the animals to which those bones aud shells belonged, ever lived in the stones, or were nourilhed by them. It is certain that they must have got into the stones before their induration. If then the jasper in question had been formed around the insects, time would consume them, the holes they occupied would remain open, and their remains in the form of dust might be found in them.
A,s to iron, which Barchewitz pretends the white ants of the East Indies live upon, the circumstance is so incredible, that it would be judging charitably of that author to suppose lie had-bej:n mistaken.
Pace 98,1. io*.
Thepdoptmlrtr. The various larvce which live in dung-