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Page 86, 1. 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 in 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 deftitute of every thing, but who foon found a retreat in Germany, in England, in the United Provinces and in Switzerland, we fhall 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 infic nitely 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 re. turn to their native country. Thus God accomplished in 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. À 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, confidering that an animal brought to life in a temperate air, and accustomed to a certain kind of food, a. pears little fit to endure the heat of our ftomach, the corro. sion of the solvent humours which enter it, the humidity and moisture with which it is filled, the trituration and great diversity of 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 say how they have got admittance otherwife, 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 áttack our dead bodies are not the same which inhabit them when living. The origin of these last is unknown to us; but we know that the first are produced from flies 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 larvæ of these flies, and according
ly they never deposit their eggs on living bedies : and it is · sufficient to prevent a dead body from being eaten by worms, to defend it from flies. As to the worms which are found in our bodies while alive, it is probable that they die with us, and that our bodies when become cold and core rupted, are incapable of preserving the life of animals accustomed to a great degree of heat and to frelh food. What confirms this idea, is, that we fee 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 of fails is very slow. The mechanisın of their progressive motion is more curious than is generally imagined, at least if it reseinbles 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 mo. tion, very regular and rapid, proceeding from the tail to the head, the undulations succeeding one another at equal diftances, 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 power than the undulatory motion, and it may be said that to advan, e one step, it must make twenty. Who could imagine that this animal runs so fast, when it proceeds so slowly!
· PAGE 89, 1. 11. . I be blind mole. Moles are by no means blind, but their eyes are not tormed to bear the light of broad day. They are very small, and deep seated; they must be fought for to be fewn. It was necessary that they should be chus hidden to
defend them from the falling in of the earth, in which this animal is continually digging. It is this wise precauvon in nature, which makes people believe that moles are blind; they would become blind if they had less the ap;earance of being so.
Page 90, l. 14. To prevent their falling to the bottom. Aquatic infects are not confined to a single mode of progreflive motion. Many walk, swim, and fly, others walk and twim, and others potless only one of thote means of motion. Of thole which swim, the greater part swim on the belly, and some on the back. Toswim the more quickly, some have the power of filling themselves with water, and of ejecting it again forcibly by the posterior extremity; this pushes them forward with an effect similarto that which puthcs back the Eolipile, or makes a rocket afcend. In this way the larvæ ofthe Libellula Puella swims. Others have the hind lgs long, and made like oars which they ule in the same way. Of those which walk, some go on the belly, others on the fides, and others on the head and the tail. Infects of this last fort have no teet, they have a sort of limb at each extremity of the body which serves them for feet, and by which they can altach 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 Strides. Many aquatic infects properly speaking neither walk nor swim ; but by a progreffive undulation of the under part of their body, they can produce the effcct. There are even fome that without the smallest observable external motion glide through the water in every direction and with great velocity. Many of these are Proteuses which change as 'it were their form at pleasure, and take such odd shapes that it one did not know them, one would never take them for animals,
PAGE 91, 1. 3. Like a bow after the arrow is let fly. What facilitates this elaftic motion is their having huoks at their anterior part by which they connect themselves with the posterior part of their hrdies. When they make an effort as if to feitore themselves at the time that they are bent double,
these hooks at once loose their hold, and cause those jerks by which the animal leaps from place to place.
PAGE 92, I. 21. Excepted from this general rule. In this example it is remarkable that the insect is a butterfly, and that butterflies 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 ; while the latter, at least the greater part of them, can fold their wings like a fan ; which may help to direct their fight.
Page 92, l. 24. The fight of the male being most rapid. There are even among butterflies and beetles fome species where the females do not fly at all, as has been already mentioned.
PAGE 26, 1. 2. They all drend the rigour of winter. The Winter how ever is formidable but to few fpecies of insects. Besides that the greater part refst the most intense cold, and that a fevere winter kills fewer 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 of eating and growing: there are many caterpillars of this kind. I am suprised to find them mentioned by no author ; probably because they have never thought of seeking for them in that severe feafon. 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 feed when it grows more moderate. It is generally towards spring, that they transform themselves into nymphs or chrysalids.
PAGE 96, l. 19. Scen asianbling in crowds. This relates only to certain species aceustomed to live in society. We do not find infects that live folitary, and which are certainly the most numerous, assembling together to pafs the winter.
PAGE 97, l. 3. * Dr Welfch mentions a beautiful jasper which on one fide had many deep and winding holes, visibly the work of
certain infects which had lived in them. Befides; a certain yellowish dust in them indicated that they could only have been the holes of worms; and Barchewitz says that a spea cies of white ants in the East Indies live on iron.
Page 63, 1. 13. Sand, Jones, iron. These substances appear so little fit to be food for insects, 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 fand, a careless observer might easily be deceived, and imagine when he sees the animal taking fand 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, or which appears to have been attacked by some insect, is not a valid proof that that insect has used it as food. Some insects indeed build the cases in whichi 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 itself in the stone? But it is not even probable that insects 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 filhes, or the animals to which those bones and shells belonged, ever lived 'in the stones, or were nourished 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 injects, time would consume them, the holes they occupied would remain open, and their remains in the form of dust might be found in them.
As to iron, which Barchewitz pretends the white ants of the East Indies live upon, the circumstance is so incredible, that it would be jindging charitably of that author to suppose he had been mistakeri.
Page 98, 1. 18.