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which would perish in fresh waters. On the other hand, the fairness of the sea would kill many which cannot, live but in fresh waters. Hot springs, in which a person cannot hold his hand without being burnt, would seem to be a very improper abode for living beings ; and yet there are insects found, which live and thrive in them, and die when taken elsewhere. It is well known that these little creatures very much dread the cold, which generally benumbs them; would one then expect to sind some in snow ? We know likewise that ofsensive smells and oily substances are injurious to them, yet some inhabit the water of dunghills, in which both these inconveniences are united. There are even Naturalists who pretend to have discovered some in sire; but I doubt the truth of their observations. Fire is an element which destroys and dissolves every thing! how then should an iustct resist its action ? It is very certain that they are found both in natural and artisicial liquors. The curious have perceived them in the bleedings of the vine newly drawn, in wine, in vinegar, and in infusions of every kind; a phenomenon the more surprising as the greatest part of insects have an aversion at every thing which is acid or pungent, as some of these liquors are. Lastly there are amphibious insects as west as other animals. Many specits live equally well in water or in air. They delight to be in the vicinity of water, on the surface of which they are seen flying, and serve for food to the animals of both elements.
The earth, both in its surface and below it, is not less peopled with numbers of insects than the waters. Some have no other domicile than below the surface of the earth; ethers may retire thither sor protection against the rigours of winter; hence many derive the names which distinguish them srom other species. For example, we call those flies, larvre and spi
K 2 ders i
ders which Hve in the earth, land insects, to distinguish" them from others of the fame kind that live elsewhere. It is not indisferent to them what foil they make use of; they are seen seeking with anxiety for that which is sittest for their purpose, and there they six. Others make vaults underground, through which they creep and walk 5 others content themselves with a hole which they fabricate with wondersul art, and in which they nedle. Grasshoppers delight in a dry foil, and crickets love to dwell in walls constructed of mud. Earth newly dug, swarms with insects, son.eof which seed on the roots of plants, and others on the earth itself. Some live only in sandy foils, Others only in that formed of rotten wood. Some lodge in the fat and putrid earth of dunghills, and sind what is necessary to lise in a place which would kill other insects. In this class 1 rank flies, some beetles, and the larvæ of dunghills. Others seek their food in the excrement of animals, and are found in it both before and after its exclusion. Some put themselves under stones which serve them as a canopy; while others gnaw them, however hard, till the,y have excavated a hole in which they can lodge. Lastly they are found in vast numbers on the surface of the earth; such are the land pulices, grasshoppers, millepiecjs, Sec.
There is hardly a plant which does not nourish some insect. Some people even affirm that each has a species of insect peculiar to itself; but it also often happens that the fame plant serves as a residence to many species of these little animals. Some creep in the grass, or construct in it dwellings for themselves. Others lodge about the roots of plants, or fabricate small apartments near them; some lastly harbour in the bulbs of flowers.
The grass is like a large carpet on which nvnv
species species of infects are found. The larvæ of -all forts of insects are found on the wormwood,- the cabbage, the borrage, the nettle, on sennel, flax, ground ivy. motherwors, chervil, mint, cress, orach, bugiofs, melilot, anile, plaintain, and spurge. Some lodge between the two membranes of the leaf; the under one serves them for a bed, the upper for a covering. Others which have derived their name from the circumstance, roll up the leaves like a cylinder; attach the different folds with a thread which they draw from themselves, and shut themselves up in it. Lastly some are found sixed on Mowers. The anemone, . the flowers of the wild cress, of hyacinths, July flow, ers, larkspurs, roses, violets &c. serve as a habitation for many species,
Nothing is secure against the voracity of these importunate guests ; they spare no sort of fruit whether dry or green. They are found not only on the leaves, thtf ears and stems of corn, but also in the dried grain; such as pease, beans, oats, &c. and |n the bread made of these', \
They mount up on shrubs and lodge there. They delight in the hawthorn, the elder, the goole-berry, the quince, the vine &c. Some keep themselves on the outside of the leaves, while others penetrate within, between the two membranes, attach themselves to the flowers or insinuate themselves into the wood itself, and there cause small excrescences.
The larger trees are worlds peopled with various species of insects, and there isihardly a partofthem which these little animals do not attack. Some that have acquired the name ot ambulones, do not consine themselves to a single tree, but go from one to another, seemingly desirous of tasting all. Others are more constant, and aitach themselves to the root, the fcark
or wood of the tree, and keep sixed there. Tha lasle of these last varies. Some preser green to rotten wood, oihers esteem dry wood besore what is moist, and are better pleased with those places in .which corruption has begun, ihan with those that are sound. Some live on the leaves of trees, as the lime, the mulberry, the alder, the willow &c. Some insinuate themselves within the parenchyma of those leaves, and live between the two membranes which cover them, while others are the cause of an excrescence in which they lodge. These are of many species; and it is easy to know them by the different /orm of ihe excrescence they live in, Some make ft of a round form either on the upper surface of the leaf, as those on the beech, or on the under surface like those of the oak; some on the margins as those of the willow, others give it the sigure of a cone like those on the' lime. The flowers 'of trees, have likewise their inhabitants. Insects are found on those of the cherry, the apple, the plumb, the hazle, &c. nay, they penetrate the fruit, and spoil our apples, pears, sigs, cherries, nuts, &c.
But it is not plants alone that insects chuse for their abode, they likewise effect a lodgement in animals and even in other insects. U is well known that the ichneumon flies lay their eggs in the bodies of caterpillars and spiders where they are afterwards hatched. Before this fact was persectly ascertained it was easy to fall into error, and to believe that one species of insects sometimes produced a species different from itself. Can we be surprised then that some naturalists mould advance this paradox? Some are found attaching themselves to the outside of another insect without penetrating further; thus we sind a fort of lice on aquatic insects, on bees, butterflies and beetles. Serpents likewise nourish many insects. I have not yet been able to
discover discover if animals covered with a hard shell, such as crabs, are insested with any sort of vermin; this is not impossible, since some writers affirm that they have found such on shell sish. Oysters are said to have insects with many seet in them, and we'see evidently that the shells of sea snails and muscles have been eaten by worms. *
Fishes though living constantly in water, and having their bodies covered with scales, are not exempt from the insults of insects; these attack, the most monstrous whale, as well a* the smallest sish. Some harbour under the scales, as under a roof;1 others attach themselves near the very eyesr and adhere so strongly, that notwithstanding the rapidity of the sish, it cannot shake them oft. Others insinuate themselves under the ears of whales, and are there nourished; others pierce the flesh, and penetrate so deeply, that they cannot be seen or expelled. Some glide into the intestines which they pervade in all directions; or settle in the stomach.
Many authors have observed that insects harbour m the seathers of birds; not however always in equal numbers; for in autumn, there are sewer of them than at any other season. The cause of this may be, that they are then fatter, and that they have imparted a good number of these attendants to the young they have hatched. Those who have the care of poultry yards, know that pullets and geese, are attacked by vermin, and this is perhaps the reason why hawks are so tormented with them. The birds they seize, communicate these vermin to them which they never can afterwards rid themselves of. If we may believe the testimony of authors, cranes have also a great number of insects adhering to them. The fame is to be said of Peacocks, and Turkies; but sew birds are more cruelly insested with them than phea^