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ENTOMOLOGY, or the doctrine of insects, constitutes the fifth class of Zoology. It is by far the most numerous class in the animal kingdom, and the most remarkable for its effects on the objects of human industry. Every insect is furnished with a head, antennæ or horns, and feet. All insects likewise have six or more feet; they respire through pores on the sides, called spiracles; and their skin is extremely hard, and serves them instead of bones, of which latter they have none internally. The head also, the trunk, the proboscis, the feelers, the breast, the belly, the limbs, the tail, and the wings are all regarded by the entomologist.

See the proud giant of the beetle race;

What shining arms his polish'd limbs encase!
Like some stern warrior formidably bright,
His steely sides reflect a gleaming light:

On his large forehead spreading horns he wears,
And high in air the branching antlers bears:

O'er many an inch extends his wide domain,

And his rich treasury swells with hoarded grain.-BARBAULd.

THE GOVERNING PRINCIPLE IN INSECTS.-Some philosophers have maintained that bees and other social insects act merely from sensation; that their sensorium is so modelled that they are impelled by a feeling of pleasure alone to the acts which it is their destiny to perform; that the succession of their different labours is preordained by the Creator; and a pleasurable sensation attached to the performance of each task; and that, consequently, when they build

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cells when they sedulously attend to the young broodwhen they collect provisions, these proceedings evince no plan, no affection, no foresight; but that the enjoyment of an agreeable sensation is the sole influencing motive which leads to the performance of each of these operations. But surely," observes Kirby, "it would be better to resolve all their proceedings at once into a direct impulse from the Creator, than to maintain a theory so contrary to fact, and which militates against the whole history which M. Huber, who adopts this theory from Bonnet, has so ably given of these creatures." That their various employments may afford them agreeable sensations, is a fact which need not be disputed; but that they act merely from the impulse of these sensations, without any plan previously concerted, seems to be contradictory both to reason and inference. That their proceedings are conducted upon a plan which does not result from mere sensation, is proved by the fact that they vary their procedings according to circumstances. Their well-known irascibility leaves no room to doubt that they are susceptible of the passion of anger; and that they are liable to be acted on by fear and alarm is universally acknowledged; and, admitting them to be susceptible of anger and fear, it does seem unreasonable to infer that they are, at the same time, incapable of feeling affection. Further, the precautions which they are known to adopt to prevent, and ward off any evils which seem to threaten them, also prove that they possess a certain degree of foresight. Without rivalling man either in intellect or feeling, they may be endowed with that measure of each which is necessary for their purposes. After all, the moving principle which impels and regulates the proceedings of the social tribes of insects, is involved in a depth of mystery which, with all our boasted advantages, we in vain attempt to fathom; the motives which urge them to fulfil, in so remarkable though diversified a way, their different destinies, baffle the researches of human sagacity. But, however impenetrable may be the veil which conceals these mysteries from our sight, one thing is clear to demonstration—that these creatures and their instincts loudly proclaim the power, wisdom, and goodness of the Great Father of the universe, and prove, beyond all cavil and doubt, the existence of a superintending Providence, which watches with incessant care over the welfare of the meanest of his creatures.

THE PAPER-MAKING INSECT.-The wasp is a papermaker, and a most perfect and intelligent one. While

mankind were arriving, by slow degrees, at the art of fabri cating this valuable substance, the wasp was making it before their eyes, by very nearly the same process as that by which human hands now manufacture it, with the best aid of chymistry and machinery. While some nations carved their records on wood, and stone, and brass, and leaden tablets; others, more advanced, wrote, with a style, on wax; others employed the inner barks of trees, and others the skins of animals, rudely prepared-the wasp was manufacturing a firm and durable paper. Even when the papyrus was rendered more fit, by a process of art, for the transmission of ideas in writing, the wasp was a better artisan than the Egyptians; for the early attempts at paper-making were so rude, that the substance produced was almost useless, from being extremely friable. The paper of the papyrus was formed of the leaves of the plant, dried, pressed, and polished; the wasp alone knew how to reduce vegetable fibres to a pulp, and then unite them by a size or glue, spreading the substance out into a smooth and delicate leaf. This is exactly the process of paper-making It would seem that the wasp knows, as the modern paper-makers now know, that the fibres of rags, whether linen or cotton, are not the only materials that can be used in the formation of paper; she employs other vegetable matters, converting them into a proper consistency, by her assiduous exertions. In some respects she is more skilful even than our papermakers, for she takes care to retain her fibres of sufficient length, by which she renders her paper as strong as she requires. Many manufacturers of the present day cut their materials into small bits, and thus produce a rotten article. One great distinction between good and bad paper is its toughness; and this difference is invariably produced by the fibres of which it is composed being long, and therefore tough; or short, and therefore friable. The wasp has been labouring at her manufacture of paper, from her first creation, with precisely the same instruments and the same materials; and her success has been unvarying. Her machinery is very simple, and therefore it is never out of order. She learns nothing, and she forgets nothing.

APHIDES.-Voracious beasts might ravage our flocks and our herds, but could scarcely by their powers accomplish greater injuries to the labours and possessions of man than the seeming despicable creatures, weevils, wire-worms, thrips, aphides, or those atoms which we denominate the blight of some seasons; and we should accustom ourselves to view no portion of creation with contempt: the particle

which we may brush away to-day with contumely, may, to-morrow, become an instrument of our punishment or ruin. Where all is wonderful, it is difficult to pronounce what is chiefly marvellous; yet the insect world exhibits most astonishing construction, viewed as to its splendour or fabrication. This feeble aphis, now crawling over my paper, with limbs indescribably slender, seems yet endowed with every requisite given to a larger body-joints, integuments, circulation of fluids, and every mechanical action requisite for its being; and yet the whole is so fragile as to be overturned by a puff of my breath. But smallness of bulk is no criterion of inferiority of power: an apple-tree, several feet, perhaps, in its circumference, spreading its branches over a rood of land, sickens and dies from the puncture of the aphis lanata, a creature so small as to be imperceptible on its limbs.

Full Nature swarms with life; one wondrous mass

Of animals, or atoms organized,

Waiting the vital breath, when parent Heaven
Shall bid His spirit blow. The hoary fen,

In putrid streams, emits the living cloud

Of pestilence. Through subterranean cells,

Where scorching sunbeams scarce can find a way,
Earth animated heaves. The flowery leaf
Wants not its soft inhabitants. Secure,
Within its winding citadel, the stone

Holds multitudes. But chief the forest-boughs,
That dance unnumbered to the playful breeze,
The downy orchard, and the melting pulp
Of mellow fruit, the nameless nations feed
Of evanescent insects. Where the pool
Stands mantled o'er with green, invisible,

Amid the floating verdure millions stray.-THOMSON.

SPIDERS.-The spider, against which there is so strange and general a prejudice, is in reality a most interesting family. One day last summer I saw a small garden-spider on the back of a lime-leaf, and by it what appeared to be a minute white blossom. I took the latter into my hand, when a friend, who was observing the movements of the little spider, remarked that it became suddenly agitated. What I had removed, was the bag that contained its eggs; I immediately replaced it. There were numerous little holes in the leaf; the spider fastened several threads to the bag, until the line was strong enough to draw it, and then, partly by drawing, and partly by pushing with its legs and body, brought it to one of the holes, and drew it through to the under side of the leaf. My friend again turned the leaf, exposing that side to the light, and the spider hastened

again to remove it into the shade. It was curious to observe that the insect not only conveyed the bag again to the other side of the leaf through one of the holes, but that it drew a line across, and passed over the hole it had drawn it through before, and conveyed it through the next. We then laid the leaf aside; and on looking at it again, some time afterwards, found the spider and its bag stationary in the very spot in which we had left it. The eggs were in the security of darkness, and it was satisfied.

THE TURNIP FLY.-The extensive ravages committed on turnip crops as soon as they appear above the ground, has been known in a single season to produce losses to our British farmers to the amount of several hundred thousand pounds. The insect usually called the fly, or black-jack, is the Haltica Nemorum of Entomologists, which eats into the seed-leaf and kills the plant.-A plan for protecting turnip crops from this insect has been successfully tried by Mr. Poppy, to whom the Highland Society voted their Ceres Medal. Observing that the fly preferred the common turnip to the Swedish, he sowed alternate drills of each, allowing half a peck of the common turnip seed to the acre as a thick sowing to attract the fly, and one pint of Swedish turnip seed to the acre, as a thin sowing to stand for a crop. The result was that the thin-sown Swedish turnips were not sensibly injured by the fly, while the thick sown ones were quite black with the swarms. When the Swedish had got into the second leaf and out of danger, the alternating rows of the common sort were ploughed in, and the crop being afterwards managed in the usual way, turned out very good, whilst all the turnip fields in the vicinity were totally destroyed. A similar experiment, tried near Blandford, in Dorsetshire, was equally successful. It is but right for us to mention, however, that this plan (at least if the alternate rows of the common turnip be ploughed in when in the second leaf) will not protect the crops from the attacks of the black grubs of one of the saw-flies, which begins its ravages in the more advanced state of the plants.

DO INSECTS FEEL PAIN?—The cruelty of collectors in tormenting insects is often a theme of reproach among those who are fond of raising objections. But it is not difficult to adduce numerous facts, proving that the converse of our great poet's conclusion,

"The poor beetle that we tread upon, In corporal sufferance, feels a pang as great

As when a giant dies."

must be nearer the truth. A humble bee, for example, will

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