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called termes, pipe-worm, or shelly ship-worm, and belongs to the next order. In both forms it is peculiarly destructive to shipping; boring its way into the stoutest oak planks, with great rapidity and facility; and chiefly forming a necessity for their being copper-bottomed. The animal is, in its habits, gregarious; and hence, in attacking a vessel, it advances in a multitudinous body, every individual punctiliously adhering to its own cell, which is separated from the adjoining by a partition not thicker than a piece of writing-paper. In a preceding lecture, however, I had occasion to observe, when glancing at the shelly ship-worm, or teredo navalis, that, by its attacking the stagnant trunks of trees and other vegetable materials, that in many parts of the world are washed or thrown down by torrents and tornadoes from the mountains, and block up the mouths of creeks and rivers, and thus powerfully contributing to the dissolution of dead vegetable matter, it produces far more benefit than evil; the benefit being universal, but the evil partial and limited. In 1731 and 1732 they appeared in great numbers on the banks of Zealand, and considerably alarmed the Dutch, lest the piles by which these banks are supported should have been suddenly destroyed. They never, however, staid long enough to commit mischief, the climate, perhaps, being too cold for them.
Another genus worthy of notice under this order is the actinia, which includes those species of naked sea-worms which are vulgarly called sea-daisy, actinia Belli); sea-carnation, a. Dianthus; sea-anemony, a. Anemonoides; and sea-marigold, a. Calendula; from their resemblance to the stems and flowers of these plants. The first three are found on the warmer rocky coasts of our own country, as those of Sussex; and the last on the shores of Barbadoes. The sea-carnation is sometimes thrown upon our flat coasts, and left evacuated of its water by the return of the tide; in which case it has the appearance of a slender, long-stalked, yellow fig.
Most of us are acquainted with some species of the sepia or cuttle-fish, which is another genus of the order before us. The common cuttle-fish, sepia officinalis, is an inhabitant of the ocean, and is preyed upon by the whale and plaise tribes; its arms are also frequently eaten off by the conger-eel, but are reproducible. The bony scale on the back is that alone which is usually sold in the shops, under the name of cuttle-fish, and is employed in making pounce. These animals have the singular power, when pursued by an enemy, of squirting out a black fluid or natural ink, which darkens the waters all around, and thus enables it to escape. This natural ink forms an ingredient in the composition of our Indian inks. The worm or fish was formerly eaten by the ancients, and is still occasionally used as food by the Italians. In hot climates, some of the species grow to a prodigious size, and are armed with a dreadful apparatus of holders, furnished with suckers, by which, like the elephant with its proboscis, they can rigidly fasten upon and convey their prey to the mouth. In the eight-armed cuttle-fish, sepia octopodia, which inhabits the Indian seas, the arms or holders are said to be not less than nine fathoms in length. In consequence of which the Indians never venture to sea without hatchets in their boats to cut off these monstrous arms, should the animal attempt to fasten upon them, and drag them under water. This genus, with that of the argonauta and nautilus, constitute the order Cephalopoda of Cuvier, which belongs to his class named Mollusc*.
The medusa is another genus entitled to attention, as affording various species that shine with great splendour in the water. The worms of this kind are vulgarly denominated sea-nettles, and consist of a tender gelatinous mass, of various figures, furnished with arms or tentacular processes, issuing from the under surface. The larger species, when touched, produce in the hand a slight tingling and redness, and hence, indeed, the name of sea-nettles, by which they are commonly distinguished. A few of the species are found on our own coasts; but by far the greater number are exotics.
The asterias, sea-star, or star-fish, is another genus of molluscous worms, and, in some of its species, is known to all of us. The most curious species of this genus is the asterias Caput Medusa, or basket-fish; which inhabits most seas, and consists of five central rays, each of which divides into two 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 Linnaean 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-pieces, 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 Mollusc*, 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
(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 thro*a 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 beari ■ 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 MiiLTivALVED Tkstaceous 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 Linnaeus 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 Order of the Linnaean 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 or Infusory Order Of Worms, comprehends those mi mite 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 Linnaean 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 characterized 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 antennae 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 scarabaeus 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 Rhyncota, 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 phalaena 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.
The Neuropterous Insects, or those with four reticulate or net-work wings, form the Fourth Order of the Linnaean class; and they maybe 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 agnathaof several 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 tracheae, or respiratory organs, are singularly placed at the verge of the tail. It is the odonata of Cuvier.
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 Linnaean 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 Onathaptera, 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 Linnaean 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