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armed with a sting, a forceps, a bristle, or a kind of claw with a moveable thumb.
Though numberless these insect tribes of air,
Peculiar beauties deck each varying frame. The legs are composed of three parts, connected to each other by joints, and represent the thighs, shanks, ankles, and feet of larger animals.
The wings of insects are so diversified in number, consistence, and colour, that Linnæus has made them the foundation of the seven orders or divisions into which he divides this numerous class of ani- . mals. Some insects are furnished with four, and others with two wings, and some of them are entirely destitute of these instruments of motion.
We'wonder at a thousand insect forms,
Various arrangements of insects have been made by náturafists, the principal of which we shall just glance at before we proceed to explain the Linnean system. Swammerdam and Ray founded their arrangements on the different changes which insects undorgo, and distribute them into four great divi
sions, agreeably to the different forms under which they appear; Valisnieri has also distributed them into four orders, but according to their habitation; arranging together in one group such as inhabit plants; placing in another, those that live in the water; and in a third, such as conceal themselves under the earth or sand; reserving for his last division, those that inhabit the bodies of other animals. All those systems are defective, in having too few divisions of a class of animals so extremely numerous; the last, however, is liable to an imperfection of another kind, because many insects change their habitation at the moment of their metamorphosis. Some are at first aquatic, but, after their transformation, are seen inhabiting the trees and plants; many of the subterraneous insects in like manner rise into the air as soon as they arrive at their winged state.
The system of Fabricius is built upon the extraordinary variety which exists in the structure of the mouth in different tribes of insects. But the distinction is not sufficiently obvious for a general classification. Other naturalists have thrown out from the province of insects many of those introduced into the apterous order of Linnæus. This has been especially done by Cuvier and Latreille, who have formed a new and an eighth order of the cancer, monoculus, and oniscus tribes, under the name of CRUSTACEA; while Lamarck is dissatisfied that the spider should be regarded as an insect, and continued in the same class'. The Linnæan arrangement is imperfect, but where shall we stop if we change it?
* We must not omit to mention that to Messrs. Kirby, Leach, and Spence, Entomology is indebted for some improvements in the Lin. næan system.
Some a twofold apparatus share,
· The Coleoptera have a hollow horny case, under which the wings are folded when not in use. The principal genera are:-1. Scarabæus, beetles.-2. Lucanus, stag-beetle'.-3. Dermestes.–4. Coccinella, lady-bird?:45. Curculio, weevil.—6. Lampyris, glow-worm 3.—7. Meloe, Spanish-fly.-8. Staphylinus.-9. Forficula, ear-wig.
Like other winged insects, all the beetles live for some time in the form of caterpillars, or grubs:
See the proud giant of the beetle race;
* See this described in Time's Telescope for 1815, p. 215.
2 On the utility of the lady-bird, consult T.T. for 1816, p. 238; and, for a poetical illustration, T.T. for 1819, p. 211.
s For a further account of the glow-worm, and poetical illustrations, see T.T. for 1814, p. 132 ; for 1815, pp. 196, 253; for 1816, p. 239; for 1817, p. 246; for 1818, p. 210; and the present vol. p. 208.
It is here worthy of remark, that the same animals, when in the state of caterpillars, live in a different manner, and feed on substances of a very different kind from those they consume after their transformation into flies. The caterpillars of the gardenbeetle, cockchafer, &c. lead a solitary life, under ground, and consume the roots of plants. Those of others feed upon putrid carcases, every kind of flesh, dried skins, rotten wood, dung, and the small insects called pucerons, or vine-fretters. But after their transformation into flies, many of the same animals, which formerly fed upon dung and putrid carcases, are nourished by the purest nectareous juices extracted from fruits and flowers. The creatures themselves, with regard to what may be termed individual animation, have suffered no alteration. But the fabric of their bodies, their instruments of motion, and the organs by which they take their food, are materially changed. This change of structure, though the animals retain their identity, produces the greatest diversity in their manners, their economy, and the powers of their bodies.
The scarabeus melolontha, or common chaffer, well known in this and other countries, flies at dusk with a rash and noisome impulse; lives upon the first budding leaves of the elm tree, and, when caught, is often tormented by children, who, placing a paper fixed with a pin at one of their legs, enjoy the cruel pleasure to see them turn round a piece of wood! It is a great pity, that in our earliest days we are not properly taught, that pleasure to one of the creation should never be sought out of the pain felt by another. There is a sort of barbarity in tormenting animals, which is too often indulged in infants, and is generally the sad prognostic of a tyrannical disposition, which grows and increases by degrees. Who ever thought that the boy, who, in the palace of the Cæsars, amused himself with the innocent pastime of torturing common flies with a pin, would, when a man, order his mother to death, and set fire to the imperial town of Rome? In these puerile trifles were concealed the dreadful stamina of the most execrable and most wanton cruelty.
Many caterpillars, previous to their transformation, live even in a different element. The ephemeron fly, when in the caterpillar state, lives no less than three years in the water, and extracts its nourishment from earth and clay. After transformation, this animal seldom exists longer than one day, during which myriads of eggs are deposited on the surface of the water. These eggs produce worms or caterpillars, and the same process goes perpetually round.
ORDER II.- hemiptera.
Some multipede, earth's leafy verdure creep,
Insects of the second order have four wings, but the upper pair, instead of being hard and horny, rather resemble fine vellum. They cover the body horizo ntally, and do not meet in al direct line, forming a ridge or suture, as in the beetle tribe. The whole of this order are furnished with a proboscis or trunk