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except in consequence of extreme cold. A moderate frost does not prevent them from moving, when they are touched; their heart or great artery, still continues to beat; but it beats much more slowly than in summer It is therefore to be presumed, that they likewise breathe in winter, but at longer intervals than in other seasons. All infects, however, do not pass the winter in such repose; there are some, for which that season is a season of activity. I know many which move, eat, and grow, at that time, and do not undergo their changes till the spring. Insects of this kind, it is obvious, must respire in winter, that being their proper season. •
Page 57,1. 14.
Couple -with the females. See on this bead, p. 290, in the 1 marks on the words, They multiply by generation.
Page 57,1. 26.
*The most common figures* The eggs of spiders, and many butterflies, are round. These eggsi, though round, are however, distinguished by a variety of appearance. They are not all smooth, but some of them carved in many difierent ways, as may be seen in those of many phaitenæ. The egi;s of many beetles are oval, and those of the Chrysoniela alparagi are of a conical form.
Page 58,1. 8.
*The matter of these eggs. The greater part of insects are oviparous. I fay the greater p;irt, because some species are viviparous, such as the aphides.—Author. The aphides, or at least many species of them, are both oviparous and viviparous. An aphis, that, during summer, has brought forth live young, lays eggs at the approach of winter, and these eggs are not hatched, till the following spring. Lycnet.
Page 59,1. 3.
*A great number of eggs. There are some insects, however, which lay hut sew eggs: the dor-beetle (Scarabæus stercorarius) lays but one: the Caflida nebulota, only iix or seven. Frisch.
The author's assertions in this note are not accurate. He refers to Frisch as his authority, who fays only, that the Scarabæus lays but one egg in one hole; and that the eggs bf the Caffida, which he found on the under side os the leaf of an Atnplex, were in patches of six or seven together.
Page 59,1. 4.
Seme hundreds. And even some thousands 5 as for example, the mother or queen bee.
Page 60,1. 3.
Which afterwards becomes the instil. If we believe Swammerdam, this obscure point is by no means the insect itself, but only its head, which sirst acquires its consistence and colour.
Page 60,1. 7.
As in a matrix. Would it hot be more natural, to com* pare this pellicle to the chorion and amnion, which enclose the foetus, than to a matrix?
Page 60,1. 15.
Till having become larger. Swammerdam likewise maintains, that the insect does not increase in the egg; but, thai its parts are there merely formed, and acquire consistence.
, Page 60,1. 18.
The little care. It is true, that most insects seem to be no otherwise concerned for their eggs, than to deposite them in places, where the young when hatched, may sind a sufficient quantity of the food that is proper ser them. And this, indeed, is all the care that is necessary for these eggs, or which* for the most part, the mothers can take of them, as many semale insects die immediately,after having excluded their eggs; This care, however, does not always stop there; for it is often accompanied with other .precautions. Many enclose their eggs in a very close silken web, others cover them with a coat of hairs, torn from their own bodies Some species glue them together, with a mass of viscid liquor, which hardening in the air, secures them from injuries. Some make oblique inciBons in a leaf, and hide an egg in each of these incisions. We sind some placing their eggs within the bark of trees, and in places where they are entirely protect* ed from the rain, from wind, and from the too-great heat of the sun. Some have the art of opening the nerves of leaves, and there laying their eggs, in such a manner, that
T t a an an excrescence Is formed round them, which serves at otictf for a shelter, and £>r food to the young msect. Some envelope their eggs with a sose .substance, which forms the sirst aliment of the young, before they are able to use more so-' ltd food, and to procure it. Lastly, others mike a hole in the earth, and after having carried thither a sufsicient quantity of proper food, deposite their eggs- But, if a great number of insects, after having thus laid their eggs in convenient places, and used the precautions I have mentioned, abandon thein to I'r»vidcncer there are some that neves leave them at all. Such, for example, are some species of spiders, that never move a step, without carrying along with them, in a kind of bag, all the eggs they nave produced. Their attachment to these eags is so great, that they expose themselves to the greatest dangers, rather than quit them. Such, likewise, are bees, wasps, hornets, and many other soris of similar insects. It is well kiv>wn, with what art they construct the ceils for their eggs, and with what care they seed their young, tifl the time when they are resdy to change into nymphs: these ate facts known to every body, and on which it would be superfluous to enlarge. The care which ants take of their young, is carried still further. They are not contented with depositing their eggs in places prepared for them on purpose, and of seeding their young, ttil the time when they are to pass into the nymph state; even then they coming to take most wondersul care of them. With what labour do they not transport them in line weather, from the b'-ttoni of their abode to the surface of the ground, that they may receive the benign insluence of the sun! "With what a'tention do they not carry therrr back to the bottom of their dwellings, when that luminary retires, or when the air begins to grow cold! What distress do they not testify, when an accident hath disturbed their nest, and scattered the nymphs! Na danger can frighten them from the places where thele nymphs are thrown. They seek them every where with anxiety, and every one is employed in collecting those which are found, and placing them under some cover till their sirst abode is-repaired, whither they are immediately transported. These disserent instances are suflicient, 1 imagine, to shews, that all insects da not abandon their eggs to chance; that there are some, which take as great, if not greater care of their voung, thai* many of the larger animals, and that even those that do a
baedea bancson their eggs, never do so, till aster having sufficiently' provided sor their preservation, and for the sustenance of the young to be excluded from them. This, indeed, the" author does not pretend to deny, as appears from the 13th chapter, which treats of the parental care which insects have of their eggs and young.
Page 6o, 1. last.
Without the affijlance of their parents. It would be a singular circumstance, if Nature had devolved on insects, the care ot hatching the eggs of sishes. This, however, is an opinion adopted by M. des Landes, with regard to the eggs of the sole, as appears by the History of the Royal Academy of Sciences for 1722, p. m. 27. It is generally believed, on the coasts of France and England, that soles are produced from a species of small sea-crab, named chevrette or erevette. M. des Landes caused a considerable quantity of these to be sished up, and put them ntJ a vessel of sea water. In twelve or thirteen days, he found in it eight or ten small soles. He repeated the experiment often, and always with the fame success. He afterwards put the soles alone, into a vessel of lea water, and though they deposited their spawn, there appeared no young soles. He found besides, that when the chevrettes were newly sistied up, several small vesicles were found among their seet, unequal in size and number, and sirmly glued to their breast, by a viscid liquor. Having examined these vesicles with a microscope, he there saw a sort of embrio, having the appearance, of a sole, whence he concludes, that the eggs of the sol*", in order to be hatched, must attach themselves to the chevrette. I will not fay, that the conclusion of M. des Landes is altogether without foundation; but I think he might have rendered his experiment much more decisive, if, instead of » the great quantity of chevrettes that he put into the vessel, and among which there might easily have been mixed a sew soles, without his perceiving them, he had contented himself with taking a sew of the chevrettes loaded with the vesicles he mentions, and putting them singly into water. If he found, then, in the course of a sew days, a small sole in the water, and at the same time, a vesicle less in those attached to that particular chevrette, it would have been a proof, that the sole was actually produced from that vesicle: But would this have been a proof, that tlie assistance of the
chevrette was indispensable to the exclusion of the sole from the egg? If the eg^s of those that spawned in the vessel remained sterile, while the others produced young* the reason of the difference might have been, either that the males had not fertilised the spawn of the former, and that they had rendered fertile that containing the eggs attached to the chevrette; or perhaps, that these eggs, needing a degree of agitation to make them hatch, the first had not in the vessel, the necessary agitation which they would have received in the sea, while the chevrettes, by their motions, would have procured a sufficient agitation to the others, i
Page 6i. 1 31.
this is so rapid. I should think it useless to observe, that the proverb here mentioned, exceedingly exaggerates the matter, if I did not know, that many people believe it literally true. It is, however, true, that of insects which are not remarkably minute, the generation of fleas, aphides, and other vermin of that fort, goes on with the -greatest rapidity. As to larger insects, a whole year is necessary for their pasting from one generation to another. The species which multiply twice a year, are in muoh smaller numbers, as are those which need more than a year to produce theif like.
Page 62,1. 4.
It is allowed, that inseBs, SsV. This is not an universal opinion. The surest way is, not to decide on a subject wt Cannot know. When we take a general view of the operations of insects, the great uhiformity, which at once appears in the economy of each species, would make Us believe, that they act merely by instinct. But, when we examine theif proceedings in detail, and when we see, that they not only vary their operations, according to the necessity of the case} but that, when they are placed in difficult circumstances, in which, according to the ordinary course of things, they should not naturally find themselves, we observe, they do not fail to make the most of thoir resources, and that ihey can, with much industry, remedy accidents, and extricate themselves from very embarrassing situations, we are then tempted to ajlow them a poi tion of reason.