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smaller ones, and each of which smaller ones again divides into two others; the same kind of division and subdivision being continued to a vast extent, and every ray regularly decreasing in size, till at length the ramifications amount to many thousands, forming a beautiful net-work spread over the water. The colour of the worm varies: being sometimes pale, sometimes reddish-white, sometimes brown.

The only other genus I shall mention under this order is the echinus, seaurchin, or hedgehog: its species are very numerous, and of a great multiplicity of forms, globular, oval, shield-like, and heart-shaped. Many of them appear to have long since become extinct, and are only to be found in a state of petrifaction. The surrounding spines form an admirable coat of mail when perfect; but they are generally broken off from the shell when it is picked up empty on our own coasts.

The THIRD ORDER of the Linnæan class of WORMS are called TESTACEA or TESTACEOUS; and comprise those that are surrounded with a shelly or testaceous covering. They are of three kinds; those possessing a single shell, of whatever form or kind, and hence denominated univalves; those possessing two shells, which are called bivalves or conchs; and those possessing more than two shells, which are in consequence named multivalves.

The UNIVALVES, or single-VALVED, are the most numerous, and exhibit the greatest variety of forms. For the most part they are regularly or irregularly spiral: among the most common of them may be mentioned the helix or snail-genus; the patella or limpet; and the turbo or wreath-genus, of which the periwinkle is a species; the animal in all which is a limax or slug. Among the more curious are, the murex or purple-shell so highly valued by the ancients for the exquisite dye it is capable of producing; the volute or mitre, including those fine polished spiral shells, without lips or perforation, which so often ornament our chimney-picces, sometimes embellished with dots, and at other times with bands of colours of various hues; the strombus, comprising the larger shells appropriated to the same purpose, spiral like the volute, but with a large expanding lip spreading into a groove on the left side, and often still farther projecting into lobes or claws, the back frequently covered with large warts or tubercles, in some species called coromant's foot; in all which, the animal or inhabitant is still a limax or slug; and the nautilus and argonauta, the pearl-nautilus and paper-nautilus; the first of which is lined with a layer of a most beautiful pearly gloss, and in the East is manufactured into drinking-cups; and the second of which is remarkable for its exquisite lightness, and the rumour common to most countries of its having given to mankind the first idea of sailing. In reality, it sails itself, and with exquisite dexterity; and to this end the animal that is usually found inhabiting the shell, and which, till of late, was supposed to be a four-armed cuttle-fish, though now regarded as an ocythoe, by Dr. Leach named o. Cranchii, in memory of the indefatigable, but unfortunate, Cranch of the British Museum, as soon as it has risen to the surface, erects two of its arms to a considerable height and throws out a thin membrane between them, thus producing a natural sail; while the oars or rudder are formed by the other two arms being thrown over the shell into the water, by which ingenious contrivance, or rather instinctive device, the paper-nautilus sails along with considerable rapidity. M. Cuvier has separated the nautilus from the rest though distinctly a univalve; and, as we have already noticed, has united it with the cuttle-fish, under an order of MOLLUSCA, which he calls CEPHALOPODA. The ordinal name for the others is with him GASTEROPODA, as most of them crawl on their bellies, and carry the shell over them as a shield. They have a distinct and moveable head, by which they essentially differ from our next order, which are without a distinct head of any kind. The two sexes are united in the same individual, but require a reciprocal union for breeding.

The BIVALVED or Two-SHELLED TESTACEOUS WORMS, the acephala or headless of Cuvier, are best explained by referring you to the oyster and the muscle

⚫ Series 1. Lecture xi. p. 118.
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(ostrea and mytilus), both which contain species that produce pearls, and mother-of-pearl; though the real pearl-muscle is amya or gaper, found chiefly on the coasts of Malabar and Ceylon, where the principal pearlfisheries are established. The species of oyster that produces small pearls is sometimes traced on our own shores, and is said to have been at one time frequent in the river Conway, in Wales. Most of the oysters cast their spawn towards the close of the spring, or in the beginning of the summer, as the month of May. This spawn is by the fishermen called SPAT, and in size and figure each resembles the drop of a candle. As soon as cast or thrown off, these embryon disks adhere to stones, old oyster-shells, pieces of wood, or whatever other substance comes in their way; a calcareous secretion issues from the surface of their bodies, and in the course of twenty-four hours begins to be converted into a shelly substance. It is two or three years, however, before they acquire their full size.

The scallops, which are a tribe belonging to the oyster kind, are capable of leaping out of the water at pleasure, to the distance of half a yard: when elevated they open their shells, and eject the water within them, and then falling back into the water close them with a loud snap.

Among the more elegant of this division is the nacre, pinna, or sea-pen, so called from its form; the animal of which (a limax or slug) secretes, as we have already observed, a large quantity of fine strong silky hair, or beard, which by the Italians is woven into a kind of silky plait. And among the most extraordinary is the gigantic chama or clamp-shell, in form resembling the oyster: one species of which we noticed not long since, as found in the Indian Ocean, of the weight of between five and six hundred pounds; the fish or inhabitant large enough to furnish a hundred and twenty men with a full meal, and strong enough to lop off a man's hand, and cut asunder the cable of a large ship.

Of the MULTIVALVED TESTACEOUS WORMS, or those containing more than two shells, there are but three known species, the chiton, the lepas or acorn-shell, and the phloas, or, as it is often improperly called, pholas, so denominated from its secreting a phosphorescent liquor of great brilliancy, which illuminates whatever it touches or happens to fall upon, and to which Linnæus chiefly ascribed the luminous appearance which the sea often assumes at a distance a subject, however, which we shall have occasion to examine hereafter.

The FOURTH CRDER of the Linnæan class of WORMS is called ZooPHYTEs, or PLANT-ANIMALS, so denominated from their efflorescing like plants. Most of them are of a soft texture, as the hydra or polype, so well known from its being capable of existing when turned inside out, and of reproducing any part of its tentacles or body when destroyed by accident. Some are corky or leathery, as different species of the alcyonium; some bibulous, as the spongia or sponge, which is now decidedly ascertained to be an animal substance; and some calcareous, as the numerous families of coral, which, under the form of tubular, starry, or stony stems, are denominated tubipores, madrepores, and isises.

The FIFTH OF INFUSORY ORDER OF WORMS, comprehends those minute and simple animalcules which are seldom capable of being traced, except by a microscope; and, for the most part, reside in putrid infusions of vegetables, or in stagnant waters filled with vegetable matter. Of these, the smallest known species is denominated monas. To a glass of the highest magnifying power it appears nothing more than a minute simple point or speck of jelly, obviously, however, evincing motion, but often from its delicacy seeming to blend itself with the water in which it swims.

Such is a bird's eye view of the Linnæan class of worms, and its five orders of intestinal, molluscous, testaceous, zoophytic, and infusory animals.

The INSECTS form the NEXT CLASS in an ascending scale; classically cha racterized as small animals, breathing through lateral spiracles, armed on all sides with a bony skin, or covered with hair; furnished with numerous feet and moveable antennæ or horns, which project from the body, and are

the probable instruments of sensation. They are so voluminous in their orders, as well as in the genera belonging to the class (this single class containing, perhaps, as many species as are known to the whole twenty-four classes of the vegetable kingdom), that our time will allow us to do little more than instance the names of a few of the most common and familiar kinds, under the ordinal arrangement. The orders are seven; all insects being included under the technical names of coleopterous, hemipterous, lepidopterous, neuropterous, hymenopterous, dipterous, and apterous; or, to exchange the Greek for English terms, under those of crustaceous-winged, half-crustaceous-winged, scaly-winged, reticulate or net-work-winged, membranaceous-winged, two-winged, and wingless. From all which it is obvious that the ordinal character of insects is derived from the general idea of wings; to which I may add, that under this general idea, while the individuals of the last order are destitute of wings, and those of the last but one are only possessed of two wings, the individuals of the preceding five orders have four wings each, though not particularly specified in their ordinal names. The COLEOPTEROUS or CRUSTACEOUS-WINGED INSECTS, Constituting the FIRST ORDER, are by far the most numerous; and, as the ordinal term imports, embrace all those whose wings are of a shelly or crustaceous hardness; and are subdistinguished by the nature of their antennas as being clubbed at the end, thread-like or bristly. Among the more familiar of this order, I may mention the scarabæus or beetle-kinds, a very numerous race, equally distinguished by the metallic lustre of their wing-shells, and their attachment to dunghills, and other animal filth. The dermestes or leather-eater, the larves or grubs of one species of which are found so perpetually to prey on the bindings of books, and sometimes even on the shelves of libraries. The coccinella or lady-bird; the curculio or weavil, the larve of which is found so frequently in our filbert and hazel-nuts, and which secretes such a quantity of bile as to give the nut a bitter taste to a considerable extent beyond the place in which it is immediately seated.

The ptinus, producing in one of its species the death-watch, is another insect belonging to this order, whose solemn and measured strokes, repeated in the dead of the night, are so alarming to the fearful and superstitious; but which, as we formerly noticed, merely proceed from the animal's striking its little horny frontlet against the bedpost it inhabits, as a call of love to the other sex. The lampyris or glow-worm, the cantharis or Spanish-fly, and the forficula or earwig: the last of which is characterized by the singularity of its brooding over its own young like a hen, and only leaving them at night, when it roams abroad in quest of food for their support. A few of these, as the lady-bird and earwig, are by M. Cuvier taken away from the present order, and, with several of the ensuing, as the cockroach, locust, and grasshopper, carried to a new order, which he has named ORNITHOPTERA.

The SECOND ORder of insects, entitled HEMIPTERA or half-crustaceous, and by some writers RHYNGOTA, has the two upper of the four wings somewhat hard or shelly, though less so than the preceding, while the two lower wings are for the most part soft and membranaceous. To this order belong the coccus or cochineal insect; the blatta or cockroach, of which the chaffer is a species; the gryllus or locust, of which one species is the little cheerful chirping cricket; the cicada or grasshopper, still more celebrated for its musical powers than the cricket; and the cimex or bug, celebrated also, but for powers which you will, perhaps, spare me from detailing.

The THIRD ORDER OF INSECTS, COLEOPTERA, or SCALY-WINGED, contains but three genera or kinds; and these are, the papilio or butterfly, the phalana or common moth, and the sphinx or hawk-moth; which last has a near resemblance to both the others, and flies with a humming noise, chiefly in the morning and evening, as the moth flies chiefly in the evening and at night, and the butterfly only in the daytime. They have all a general resemblance to each other, and feed equally on the nectary of flowers: the antennas of the butterflies are mostly knobbed or clubbed at the tip; those of the moths are moniliform, those of the sphinxes tapering.

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The NEUROPTEROUS INSECTS, or those with four reticulate or net-work wings, form the FOURTH ORDER of the Linnæan class; and they may be exemplified by the ephemera and hemerobius, the day-fly and May-fly of the angler, those little busy insects that surround us in countless multitudes when we walk on the banks of a river in a fine summer's evening, and the whole duration of whose life, in a perfect state, seldom exceeds two days, and often not more than as many hours; while it has comparatively a long life in its imperfect state, or previous to its metamorphosis. It is the agnatha of seve. ral entomologists. This order is not numerous, and I will therefore only add another example, the libellula or large dragon-fly, so denominated from its ferocity towards smaller insects; usually seen over stagnant waters; the more common species, libellula Virgo, possessing a beautiful, glittering, and green-blue body, with wings bluish towards the middle. The larve in its internal parts, is larger than the insect, and catches its prey at a distance, by suddenly darting forward the lower lip. The trachea, or respiratory organs, are singularly placed at the verge of the tail. It is the odonata of Čuvier.

The FIFTH ORDER OF INSECTS Comprises the HYMENOPTERA, the piezata of some entomologists, or those possessed of four membranaceous wings, most of which are armed with a sting at the tail. They of course include the apis and vespa, or wasp and bee. To which I may add the formica or ant, the ichneumon, and the cynips or gall-fly, to which we are indebted for our gallnuts, whose peculiarities and habits I shall hereafter have an opportunity of reverting to.

The SIXTH ORDER OF INSECTS is denominated DIPTERA, and deviates from all the preceding in possessing only two wings instead of four. It includes among others the musca or common fly, the hippobosca or horse-fly, the oestris or gad-fly, the tipula or father-long-legs, and the culex or gnat. It is subdistinguished into such animals as possess a sucker with a proboscis, and such as possess a sucker without a proboscis. This order is the antliata of some entomologists.

The LAST ORDER OF INSECTS differs still more largely from all that have been hitherto noticed; for it consists of those kinds that have no wings whatever, and hence the class is called APTERA Or wingless. To this order belong most of those insects that are fond of burrowing in animal filth upon the animal surface; as the pulex, pediculus, and acarus, the flea, louse, and itch-insect. To the same order belongs also the aranea or spider; the oniscus, wood-louse or millepede; the scorpio or scorpion, and even the cancer or crab, and lobster; the Linnæan system making no distinction between land and water animals from the difficulty of drawing a line; of which, indeed, the cancer genus is a very striking example, since one of the species, cancer curicola or land-crab, is, as we have already seen, an inhabitant of woods and mountains, and merely migrates to the nearest coast once a year for the purpose of depositing its spawn in the waters. These, however, are separated from the class of insects in M. Cuvier's classification, and form a distinct class by themselves under the name of CRUSTACEA; while the greater part of the rest, as spiders, water-spiders, spring-tails, millepedes, centipedes, and scorpions, are also carried to a distinct order of the insect class, which he has called GNATHAPTERA, leaving to his own order of APTERA nothing more than the first three of the preceding list, the flea, louse, and tick or itch-insect.

But of all the animals belonging to this division under the Linnæan classification, I should mention, perhaps, on account of its singular instinctive faculties, the termes or white ant. The kind which inhabits India, Africa, and South America is gregarious, and forms a community, far exceeding in wisdom and policy the bee, the ant, or the beaver. The houses they build have the appearance of pyramids, of ten or twelve feet in height; and are divided into appropriate apartments, magazines for provisions, arched chambers, and galleries of communication. The walls of all these are so firmly cemented that they will bear the weight of four men without giving way; and on the plains of Senegal, the collective pyramids appear like villages of the natives. Their powers of destruction are equal to those of architecture; for

so rapidly and dexterously will they destroy, in less bodies, food, furniture, books, clothes, and timber of whatever magnitude, leaving in every instance the merest thin surface, that a large beam will in a few hours be eaten to a shell not thicker than a page of writing paper.

It was my intention to have finished our survey of the Linnæan system in the course of the present lecture; but the prospect swells so widely before us that it is impossible; and the remaining four classes of fishes, amphibials, birds, and mammals must be reserved for another study.

In the mean time, allow me to remark, that low and little as the tribes we have thus far contemplated may appear, they all variously contribute to the common good of animal being, and aid, in different ways, the harmonious circle of decomposition, renovation, and maturity of life, health, and enjoyment. The insect tribes, beautiful as they are in their respective liveries, may be regarded as the grand scavengers of nature. Wherever putridity is to be found, they are present to devour the substance from which it issues; and such is the extent and rapidity of their action, that it has been calculated by some naturalists that the progeny of not more than a dozen flies will consume a dead carcass in a shorter space than a hungry lion. Thus, while they people the atmosphere they purify it; and in many instances, perhaps, and by tribes invisible to the naked eye, purge it of those noxious particles with which it is often impregnated, and which, at certain seasons, are apt to render it pestilential.

The indefatigable labour of the worm-tribes in promoting the general good is still more striking and manifest. The gordius or hair-worm perforates clay to give a passage to springs and running water; the lumbricus or earthworm pierces the soil that it may enjoy the benefit of air, light, and moisture; the terebella and terredo, the naked ship-worm and the shelly ship-worm, penetrate dead wood, and the phloas and mytilus, rocks, to effect their dissolution; while the termes or white ant, as we have just observed, attacks almost every thing within its reach, animal, vegetable, or mineral, with equal rapacity, and reduces to its elementary principles whatever has resisted the assault of every other species. The same system of warfare is, indeed, pursued among themselves; yet it is pursued, not from hate, as among mankind, but from instinct, and as the means of prolonging and extending as well as of diminishing and cutting short the term of life and enjoyment.

It has often been urged against the goodness, and sometimes against the existence, of the Deity, that the different tribes of animals are, in this manner, allowed to prey upon one another as their natural food, and that a large part of the globe is covered with putrid swamps, or wide inhospitable forests, or merely inhabited by ravenous beasts and deadly serpents.

Presumptuous murmurers! and what would your wisdom advise, were Providence to consult you upon so glaring an error? Would you then leave every rank of animals to perish by the mere effects of old age? With the example so often before you of the misery endured by a favourite horse or a favourite dog when suffered to drain out the last dregs of existence in the midst of ease he cannot enjoy, and of food he cannot partake of,—a misery which often compels us, as an act of mercy, to anticipate his fate, even at last, by the aid of violence,-would you abandon every animal to the same wretchedness, only a hundred-fold multiplied by the horrors of want and hunger, which he must, by growing every day more infirm, be every day growing more incapable of appeasing ?-Or would you cut short the evil at once, by destroying death itself, and thus rendering every animal immortal? They would not thank you for such an interference, nor applaud the vain benevolence that might dictate it; an interference which, by preventing the necessity for offspring, would extirpate from the animal frame its best feelings; which would extinguish the wise and harmonious distribution into sexes; and make an equal inroad on the pleasures of sense and the endearments of instinct.

It is granted, that a great part of the globe is an inhospitable wilderness; that it consists, to a considerable extent, of waste inaccessible jungle overrun

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