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d. Neuroptera : insects having four wings in. terwoven with veins, like a piece of net-work, and no sting.
e. Hymenoptera, insects agreeing in their characteristics with the preceding, except that these are armed with a sting.
f. Diptera, insects having two wings, and two elevated alteres (or balances) behind each.
g. Aptera, insects destitute of wings.
494. Every insect is furnished with a head, antenuæ, or horns, and feet. All insects, likewise, have six or more feet. They respire through pores on their sides, called spiracles. Their skin is extremely hard, and serves them instead of bones, of which they have none.
The head also, the trunk, the proboscis, the feelers, the breast, the belly, the limbs, the tail, and the wings, are all objects of notice to the entomologist.
See the proud giant of the beetle-race!
BARBAULD 495. Worms are, according to the Linnean system, the sixth class. Some of them have only two senses; others, no head; and most of them, no feet.
They are divided into tive orders:
1. Intestinal norms; as tape-worms, leechen, de.
2. Molluscous worms; chiefly inhabiting the sea.
3. Testaceous worms; as muscles, cockles, oysters, snails, &c.
4. Zoophytes; between animals and vegetables.
And 6. Animalcules; generally invisible to the naked eye.
496. The Indian thread-worm eats into the skin in the West-Indies, and its extraction oogasions great trouble. The furia does the same in Sweden. The common hair-worn is said to occasion whitlows. Garden, or dew-worms, sie useful to vegetation, by lovsening the soil. The heads and tails of snails will grow again. The Nereis is the sea glow-worn.
Full Nature swarms with life : one wondroun masa
497. Young snails come fortlı with their shells on their backs; and the shells arc enlarged with the animal, by means of a secretion for the par
pose, hy which also they repair the shells when hroken. The shell so effectually preserves them, that they have revived in water after being kept dry in a box for twenty years; and even after being immersed in boiling water.
Corals are shells produced by an insect within them; and they grow in such quantities, and to such heights in some seas, as to create islands inhabited by men. The friendly Islands, in the Pacific Ocean, were thus raised by corals from the depth of that sea. Ships baie osien been lost on coral-rocks.
Ods 1.-The wisitom of BECS, the harmony of their hvernment, their persevering industry, and wonderful economy, have been relebrated in every agr. Their conths, or nests, are cowposed of cells or six-sided ligurer, so finely finished, that the most expert workmans would #ind himself unqualified to consiruet a similar habitation. By applying hexagonal cells to the sidex of much other, na void spaces are left between them; and, though the same end might be accomplished by other figures, yet they would require a greater quantity of war. A comb c011sists of two rows of celle applied to each other's ends. This arrangement bord saves room in the live, and gives a double entry into the cells: the basis of the cells in one row of a comb, serving for baset to the opposite row. Il is dificult to perecive, rven with the desistaner of glasse hives, the manner in whicli hers operate. They are so eager to aitort mutual assistance; and, for this purpose, Ao many of the crowd togrther, that their individual operations can seldom be observert. It has, however, been discovereil, that their own cerih are the incrumente they employ in modelling and polishing the way. The combs are generally arranged in a direction parallel 10 vach other. An interval, or srert, between the comhu, in always left, that the hero nins have a fer passage and an easy romniunication with the Historant combs in the hive. These street are sushiently wide, to allow tow
been to pano one another. Beside these parallel streets to shorten their journey when working, ihey leave seve ral round cross panunge, which are always covered, 'The honeybees not only labour in common with astonishing aswidaity and art, but their whole attention and a fl'ections perm to centre in the person of the Qureu or sovereign of the live. When by any accident she dien, the whole community are instantly in disorder -all their labours cente, no new orlls are constructed, and neither honey nor wax are collected,
To their delicious task the fervent becs
THOMSON, 8.-The labours of WASP9, though not beneficial to mankind, are not lens ingenious nor less worthy of admin ration, Wasps associate in great numbers, and construct a common habitation with much dexterity and skill, The cells of the waxps are formed of a kind of paper, whicb, with great dexterity, is fabricated by the animals them. selves. The hole which leads to a wasp's nest is about an inch in diameter, being a kind of gallery mined by the insects the whole nest is of a roundish form, and sometimes above twelve inches in diameter. This subter. raneous city, though amall, in extremely populous 1 in 4 middle-sized meat there were at least 10,000 cells. The different stories of combs are always about ball an loch bigh, these intervale nre so spacious, in proportion 10 the bulk of the animals, that they may be compared to great halls, or brond streets. Raph of the larger comba To mupported by about Afty pillars, which, at the same 1 Oline, kive solidity to the fabric, and greatly ornament the whole nent. Boys, and even men, are guilty of great and nudeserved cruelty to theue ingrofous inserts, who nevar sting, unless they are irritated and atincked,
S.-The uwociation of ANTS merita no lene admiration
than those of hees and wasps. The form of their nest, or hill, is somewhat conical; and, of course, the water, when it rains, runs easily off, without penetrating their abode. Under this hill, there are many galleries or pas. sages, which coinmunicate with each other, and resemble the streets of a city. They go to great distances in search of provisions; and their roads, which are often winding and involved, all terminate in the nest.
498. The study of Shells is called Conchology. There are more ihan a thousand species of shells, and they are separated into three divisions --multivalves, bivalves, and univalves, accordingly as the shells consist of many parts, of two, or of a single part.
Mullivalves consist of many plates or shells, connected in some species like the different parts of a coat of mail.
Bivalves consist of two shells, connected by a hinge; as the muscle, oyster, &c.
And the Univalves comprehend those that have a regular spiral, which is a numerous division, including the snail, periwinkle, &c., and those also without a regular spiral.
Obs.--- Pearls are found in oysters and muscles. They are calcareous concretions, formed of the liquid of which the inner surface of the shell is composed, and are an effect of accidental injury to the shell, The Chinese increase the number of pearls, by catching muscles, and perforating the shells; and then replace the muscles in the water. After is certain time, on opening them again, they discover pearls attached to the part injured. The substance of the shells of these animals, when chemically examined, is found to be a mild calcareous earth, deposited in a mass of net-work, composed of animal matier. The shining matier, left in the tracks of snails, is this very substance ; which, when deposited in strata above onc another, hardens and forms a stiell.