the water.

by an anchor. As they come to maturity they sink deeper, and at last, when they leave the eggs as worms they creep at the bottom. They now make themselves lodgments of cement, which they fasten to some solid body at the very bottom of the water-unless by accident they meet with a piece of chalk, which, being of a soft and pliant nature, gives them an opportunity of sinking a retreat for themselves where nothing but the claws of a cray-fish can possibly molest them. The worm afterwards changes its form. It appears with a large head and a tail invested with hair, moistened with an oleaginous liquor, which she makes use of as a cork to sustain her head in the air and her tail in the water, and to transport her from one place to another. When the oil with which her tail is moistened begins to grow dry, she discharges out of her mouth an unctuous humour, which she sheds all over her tail, by virtue whereof she is enabled to transport herself where she pleases without being either wet or any way incommoded by The guat in her second state is, properly speaking, in the form of a nymph, which is an introduction or entrance into new life. In the first place she livests herself of her second skin; in the next she resigns her eyes, her atennæ, and her tail; in short, she actually seems to expire. However, from the spoils of the amphibious animal a little winged insect cuts the air, whose every part is active to the last degree, and whose whole structure is the just object of our admiration. Its little head is adorned with a plume of feathers, and its whole body invested with scales and hair to secure it from any wet or dust. She makes trial of the activity of her wings by rubbing them either against her body or her broad side-bags, which keep her in an equilibrium. The furbelow, or little border of fine feathers which graces her wings, is very curious, and strikes the eye in the most agreeable manner. There is nothing, however, of great importance to the gnat but her trunk, and that weak implement may justly be deemed one of Nature's master-pieces. It is so very small, that the extremity of it can scarcely be discerned through the best microscope that can be procured. That part which is at first obvious to the eye is nothing but a long scaly sheath under the throat. At near the distance of two-thirds of it there is an aperture through which the insect darts out four stings, and afterwards retracts them. One of which, however sharp and active it may be, is no more than the case in which the other three lie concealed, and run in a long groove. The sides of these stings are sharpened like two-edged swords; they are likewise barbed, and have a vast number of cutting teeth towards the point, which turns up like a hook, and is fine beyond expression. When all these darts are stuck into the flesh of animals, sometimes one after another and sometimes all at once, the blood and humours of the adjacent parts must unavoidably be extravasated; upon which a tumour must consequently ensue, the little orifice whereof is closed up by the compression of the external air. When the guat, by the point of her case, which she makes use of as a tongue, has tasted any fruit, flesh, or juice that she has found out, if it be a fluid, she sucks it up without playing her darts into it; but in case she finds the least obstruction by any flesh whatever she exerts her strength, and pierces through it if she possibly can. After this she draws back her stings into their sheath, which she applies to the wound in order to extract, as through a reed, the juices which she finds enclosed. This is the instrument with which the gnat performs her work in the summer, for during the winter she has no manner of occasion for it. Then she ceases to eat, and spends all that tedious season either in quarries or in caverns, which she abandons at the return of summer, and flies about in search after some commodious ford or standing water, where she may produce her progeny, which would be soon washed away and lost by the too rapid motion of any

running stream. The little brood are sometimes so numerous that the very water is tinged according to the colour of the species as green, if they be green, and of a sanguine hue if they be red.

These are circumstances sufficiently extraordinary in the life of this little animal, but it offers something still more curious in the method of its propagation. However similar insects of the gnat kind are in their appearance, yet they differ widely from each other in the manner in which they are brought forth; for some are oviparous, and are produced from eggs; some are viviparous, and come forth in their most perfect form; some are males, and unite with the female; some are females, requiring the impregnation of the male; some are of neither sex, yet still produce young without any copulation whatsoever. This is one of the strangest discoveries in Natural History! A gnat separated from the rest of its kind, and enclosed in a glass vessel, with air sufficient to keep it alive, shall produce young, which also, when separated from each other, shall be the parents of a numerous progeny. Thus, down for five or six generations do these extraordinary animals propagate without the use of copulation, without any congress between the male and the female, but in the mauner of vegetables-the young bursting from the body of their parents without any previous impregnation. At the sixth generation, however, their propagation stops; the guat no longer produces its like from itself alone, but requires the access of the male to give it another succession of fecundity.

The gnat of Europe gives but little uneasiness; it is sometimes heard to hum about our beds at night, and keeps off the approaches of sleep by the apprehension it causes; but it is very different in the ill-peopled regions of America, where the waters stagnate and the climate is warm, and where they are produced in multitudes beyond expression. The whole air is there filled with clouds of these famished insects; and they are found of all sizes, from six inches long to a minuteness that even requires the microscope to have a distinct perception of them. The warmth of the mid-day sun is too powerful for their constitution; but when the evening approaches neither art nor flight can shield the wretched inhabitants from their attacks; though millious are destroyed, still millions more succeed, and produce unceasing torments. The native Indians, who anoint their bodies with oil, and who have from their infancy been used to their depredations find them much less inconvenient than those who are newly arrived from Europe; they sleep in their cottages all over with thousands of the gnat kind upon their bodies, and yet do not seem to have their slumbers interrupted by their cruel devourers. If a candle happens to be lighted in one of those places, a cloud of insects at once light upon the flame and extinguish it; they are therefore obliged to keep their candles in glass lanthorns-a miserable expedient to prevent an unceasing calamity.

BOOK V.-CHAP. I.

OF ZOOPHYTES IN GENERAL.

We now come to the last link in the chain of Animated Nature-to a class of beings so confined in their powers, and so defective in their formation, that some historians have been at a loss whether to consider them as a superior rank of vegetables, or the humblest order of the animated tribe. In order, therefore, to give them a denomination agreeable to their existence, they have been called zoophytes-a name implying vegetable nature endued with animal life; and indeed, in some the marks of the animal are so few that it is difficult to give their place in Nature with precision, or to tell

whether it is a plant or an insect that is the object of our consideration.

Should it be asked what it is that constitutes the difference between animal and vegetable life, what it is that lays the line that separates those two great kingdoms from each other, it would be difficult-perhaps we should find it impossible-to return an answer. The power of motion cannot form this distinction, since some vegetables are possessed of motion, and many animals are totally without it. The sensitive plant has obviously a greater variety of motion than the oyster or the pholas, The animal that fills the acorn-shell is immoveable, and can only close its lid to defend itself from external injury; while thie flower which goes by the name of the fly-trap seems to close upon the flies that light upon it, and that attempt to rifle it of its honey. The animal in this instance seems to have scarce a power of selfdefence the vegetable not only guards its possessions, but seizes upon the robber that would venture to invade them. In like manner, the methods of propagation give no superiority to the lower rank of animals. On the contrary, vegetables are frequently produced more conformably to the higher ranks of the creation; and though some plants are produced by cuttings from others, yet the general manner of propagation is from seeds laid in the womb of the earth, where they are hatched into the similitude of the parent plant or flower. But a most numerous tribe of animals have lately been discovered which are propagated by cuttings, and this in so extraordinary a manner, that, though the original insect be divided into a thousand parts, each, however small, shall be formed into an animal entirely resembling that which was at first divided; in this respect, therefore, certain races of animals seem to fall beneath vegetables by their more imperfect propagation.

What, therefore, is the distinction between them-or are the orders so intimately blended as that it is impossible to mark the boundaries of each? To me it would seem that all animals are possessed of one power of which vegetables are totally deficient-I mean either the actual ability or an awkward attempt at self-preservation, However vegetables may seem possessed of this important quality, yet it is with them but a mechanical impulse, resembling the raising one end of the lever when you depress the other; the sensitive plant contracts and hangs its leaves indeed when touched, but this motion no way contributes to its safety; the fly-trap flower acts entirely in the same manner; and though it seems to seize the little animal that comes to annoy it, yet in reality it only closes mechanically upon it, and this enclosure neither contributes to its preservation nor its defence, But it is very different with insects, even of the lowest order; the earth-worm not only contracts but hides itself in the earth, and escapes with some share of swiftness from its pursuers. The polypus hides its horns; the star-fish contracts its arms upon the appearance even of distant dangers; they not only hunt for their food but provide for their safety, and how ever imperfectly they may be formed, yet still they are in reality placed many degrees above the highest vegetable of the earth, and are possessed of many animal functions, as well as those that are more elaborately formed.

But though these be superior to plants, they are very far beneath their animated fellows of existence. In the class of zoophytes we may place all those animals which may be propagated by cuttings, or in other words which, if divided into two or more parts, each part in time becomes a separate and perfect animal; the head shoots forth a tail, and on the contrary, the tail produces a head; some of these will bear dividing but into two parts such is the earthworm; some may be divided into more than two, and of this kind are many of the star-fish; others still may be cut into a thousand parts, each becoming a perfect animal; they may be turned inside out

like the finger of a glove-they may be moulded into all manner of shapes, yet still their vivacious principle remains, still every single part becomes perfect in its kind, and after a few days' existence exhibits all the arts and industry of its contemptible parent! We shall therefore divide zoophytes according to their several degrees of perfection-namely, into worms, star-fish, and polypi; contenting ourselves with a short review of those nauseous and despicable creatures that excite our curiosity chiefly by their imperfections. It must not be concealed, however, that much has of late been written on this part of natural history. A new mode of animal production could not fail of exciting not only the curiosity but the astonishment of every philosopher; many found their favourite systems totally overthrown by the discovery, and it was not without a wordy struggle that they gave up what had formerly been their pleasure and their pride. At last, however, conviction became too strong for argument; and a question which owed its general spread rather to its novelty than to its importance, was given up in favour of the new discovery.

The first in the class of zoophytes are animals of the worm kind, which, being entirely destitute of feet, trail themselves along upon the ground, and find themselves a retreat under the earth or in the water. As these, like serpents, have a creeping motion, so both in general go under the common appellation of reptiles-a loathsome, noxious, malignant tribe, to which man by nature as well as by religion has the strongest antipathy. But though worms as well as serpents are mostly without feet, and have been doomed to creep along the earth on their bellies, yet their motions are very different. The serpent, as has been said before, having a back-bone which it is incapable of contracting, bends its body into the form of a bow, and then shoots forward from the tail; but it is very different with the worm, which has a power of contracting or lengthening itself at will. There is a spiral muscle that runs round its whole body from the head to the tail, somewhat resembling a wire wound round a walking-cane, which, when slipped off, and one end extended and held fast, will bring the other nearer to; in this manner the earthworm having shot out or extended its body, takes hold by the slime of the fore part of its body, and so contracts or brings forward the hinder part; in this manner it moves onward, not without great effort, but the occasions for its progressive motion are few.

As it is designed for living under the earth and leading a life of obscurity, so it seems tolerably adapted to its situation. Its body is armed with small, stiff, sharp burrs or prickles, which it can erect or depress at pleasure; under the skin there lies a slimy juice, to be ejected as occasion requires, at certain perforations between the rings of the muscles, to lubricate its body and facilitate its passage into the earth. Like most other insects it has breathing-holes along the back adjoining each ring; but it is without bones, without eyes, without ears, and, properly, without feet. It has a mouth, and also an alimentary canal, which runs along to the very point of the tail. In some worms, however, particularly such as are found in the bodies of animals, this canal opens towards the middle of the belly at some distance from the tail. The intestines of the earthworm are always found filled with a very fine earth, which seems to be the only nourishment these animals are capable of receiving.

The animal is entirely without brain, but near the head is placed the heart, which is seen to beat with a

very distinct motion, and round it are the spermatic vessels, forming a number of globules containing a milky fluid, which have an opening into the belly not far from the head: they are also often found to contain a number of eggs, which are laid in the earth, and are hatched in twelve or fourteen days into life by the genial warmth of their situation; like snails, all these animals unite in themselves both sexes at once-the reptile that impregnates being impregnated in turn: few that walk out but must have observed them, with their heads laid against each other, and so strongly attached that they suffer themselves to be trod upon.

When the eggs are laid in the earth-which in about fourteen days, as has been said, are hatched into maturity-the young ones come forth very small but perfectly formed, and suffer no change during their existence: how long their life continues is not well known, but it certainly holds for more than two or three seasons. During the winter they bury themselves deeper in the earth, and seem in some measure to share the general torpidity of the insect tribe. In spring they revive with the rest of Nature, and on those occasions a moist or dewy evening brings them forth from their retreats for the universal purpose of continuing their kind. They chiefly live in a light, rich, and fertile soil, moistened by dews or accidental showers, but avoid those places where the water is apt to lie on the surface of the earth, or where the clay is too stiff for their easy progression under-ground.

Helpless as they are formed, yet they seem very vigilant in avoiding those animals that chiefly make them their prey, particularly the mole, who feeds entirely upon them beneath the surface, and who seldom ventures, from the dimness of its sight, into the open air; him they avoid by darting up from the earth the instant they feel the ground move; and fishermen, who are well acquainted with this, take them in what numbers they choose by stirring the earth where they expect to find them. They are also driven from their retreats underground by pouring bitter or acrid water thereon, such as that water in which green walnuts have been steeped, or a lye made of pot-ashes.

Such is the general outline of the history of these reptiles, which, as it would seem, degrades them no way beneath the rank of other animals of the insect creation; but we now come to a part of their history which proves the imperfection of their organs, from the easiness with which these little machines may be damaged and repaired again. It is well known in mechanics that the finest and most complicated instruments are the most easily put out of order, and the most difficultly set aright; the same also obtains in the animal machine. Man, the most complicated machine of all others, whose nerves are more numerous and powers of action more various, is most easily destroyed: he is seen to die under wounds which a quadruped or a bird could easily survive; and as we descend gradually to the lower ranks, the ruder the composition the more difficult it is to disarrange it. Some animals live without their limbs, and often are seen to reproduce them; some are seen to live without their brain for many weeks together; caterpillars continue to increase and grow large though all the nobler organs are entirely destroyed within; some animals continue to exist though cut in two, their nobler parts preserving life, while the others perish that were cut away; but the earth-worm and all the zoophyte tribe continue to live in separate parts, and one animal by the means of cutting is divided into two distinct existences, sometimes into a thousand!

There is no phenomenon in all Natural History more astonishing than this, that man, at pleasure, should have a kind of creative power, and out of one life make two, each completely formed, with all its apparatus and functions each with its perceptions and powers of motion and self-preservation, each as complete in all

respects as that from which it derived its existence, and equally enjoying the humble gratifications of its nature. When Des Cartes first started the opinion that brutes were machines the discovery of this surprising propagation was unknown, which might in some measure have strengthened his fanciful theory. What is life in brutes, he might have said, or where does it reside? In some we find it so diffused, that every part seems to maintain a vivacious principle, and the same animal seems possessed of a thousand distinct irrational souls at the same time. But let us not, he would say, give so noble a name to such contemptible powers, but rank the vivifying principle in these with the sap that rises in vegetables, or the moisture that contracts a cord, or the heat that puts water into motion! Nothing, in fact, deserves the name of soul but that which reasons, that which understands, and, by knowing God, receives the mark of its currency, and is minted with the impression of its great Creator!

Such might have been the speculations of this philosopher. However, to leave theory, it will be sufficient to say that we owe the first discovery of this power of reproduction in animals to Mr. Trembley, who first observed it in the polypus; and after him, Spalanzani and others found it taking place in the earth-worm, the sea-worm, and several other ill-formed animals of a like kind, which were susceptible of this new mode of propagation. This last philosopher has tried several experiments upon the earth-worm, many of which succeeded according to his expectation; every earth-worm, however, did not retain the vivacious principle with the same obstinacy; some when cut in two were entirely destroyed; others survived only the nobler part; and while the head was living the tail entirely perished, and a new one was seen to emerge from the extremity. But what was most surprising of all, in some, particularly in the small redheaded earth-worm, both extremities survived the operation; the head produced a tail with the anus, the intestines, the annular muscles, and the prickly beards; the tail part, on the other hand, was seen to shoot forth the nobler organs, and in less than the space of three months sent forth a head and a heart, with all the apparatus and instruments of generation. This part, as may easily be supposed, was produced much more slowly than the former-a new head taking above three or four months for its completion, a new tail being shot forth in less than as many weeks. Thus two animals by dissection were made out of one, each with their separate appetites, each endued with life and motion, and seemingly as perfect as that single animal from whence they derived their origin.

What was performed upon the earth-worm was found to obtain also in many other of the vermicular species. The sea-worm, the white water-worm, and many of those little worms with feelers found at the bottom of dirty ditches-in all these the nobler organs are of such little use, that if taken away the animal does not seem to feel the want of them; it lives in all its parts and in every part; and by a strange paradox in Nature, the most useless and contemptible life is of all others the most difficult to destroy.

CHAP. III.

OF THE STAR-FISH.

The next order of zoophytes is that of the star fisha numerous tribe, shapeless and deformed, assuming at different times different appearances. The same animal that now appears round like a ball shortly after flattens as thin as a plate. All of this kind are formed of a semi-transparent gelatinous substance, covered with a thin membrane, and to an inattentive spectator often ap

pear like a lump of inanimate jelly, floating at random upon the surface of the sea, or thrown by change on shore at the departure of the tide. But upon a more minute inspection they will be found possessed of life and motion-they will be found to shoot forth their arms in every direction, in order to seize upon such insects as are near, and to devour them with great rapacity. Worms, the spawn of fish, and even muscles themselves, with their hard resisting shell, have been found in the stomachs of these voracious animals; and what is very extraordinary, though the substance of their own bodies be almost as soft as water, yet they are no way injured by swallowing these shells, which are almost of a stony hardness. They increase in size as all other animals do. In summer, when the water of the sea is warmed by the heat of the sun, they float upon the surface, and in the dark they send forth a kind of shining light resembling that of phosphorus. Some have given these animals the name of sea-nettles, because they burn the hands of those that touch them as nettles are found to do. They are often seen fastened to the rocks and to the largest sea-shells, as if to derive their nourishment from them. If they be taken and put into spirit of wine they will continue for many years entire, but if they be left to the influence of the air, they are in less than four and twenty hours melted down into limpid and offensive water.

In all of this species none are found to possess a vent for their excrements, but the same passage by which they devour their food serves for the ejection of their fæces. These animals, as was said, take such a variety of figures, that it is impossible to describe them under one determinate shape; but in general their bodies resemble a truncated cone, whose base is applied to the rock to which they are found usually attached. Though generally transparent, yet they are found of different colours some inclining to green, some to red, some to white, and some to brown. In some their colours appear diffused over the whole surface, in some they are olten streaked, and in others often spotted. They are possessed of a very slow progressive motion, and in fine weather they are continually seen stretching out and fishing for their prey. Many of them are possessed of a number of long, slender filaments, in which they entangle any small animals they happen to approach, and thus draw them into their enormous stomachs, which fill the whole cavity of their bodies. The harder shells continue for some weeks undigested, but at length they undergo a kind of maceration in the stomach, and become a part of the substance of the animal itself. The indigestible parts are returned by the same aperture by which they were swallowed, and then the star-fish begins to fish for more. These also may be cut in pieces, and every part will survive the operation-each becoming a perfect animal, endued with its natural rapacity. Of this tribe the number is various, and the description of each would be tedious and uninstructing; the manners and nature of all are nearly as described; but I will just make mention of one creature, which, though not properly belonging to this class, yet is so nearly related, that the passing it in silence would be an unpardonable omission.

Of all other animals the cuttle-fish, though in some respect superior to this tribe, possesses qualities the most extraordinary. It is about two feet long, covered with a very thin skin, and its flesh composed of a gelatinous substance, which, however, within-side is strengthened by a strong bone, of which such great use is made by the goldsmiths. It is possessed of eight arms, which it extends, and which are probably of service to it in fishing for its prey; while in life it is capable of lengthening or contracting these at pleasure, but when dead they contract and lose their rigidity. They feed upon small fish. which they seize with their arms; and they are bred from eggs laid upon the weeds along the sea-shore.

The cuttle-fish is found along many of the coasts of Europe, but is not easily caught, from a contrivance with which they are furnished by Nature; this is a black substance of the colour of ink, which is contained in a bladder generally on the left-side of the belly, and which is ejected in the manner of an excrement from the anus. Whenever, therefore, this fish is pursued, and when it finds a difficulty of escaping, it spurts forth a great quantity of this black liquor, by which the waters are totally darkened, and then it escapes by lying close at the bottom. In this manner the creature finds its safety, and men find ample cause for admiration, from the great variety of stratagems with which creatures are endued for their peculiar preservation.

Those animals which we have described in the last chapter are variously denominated. They have been called the star-fish, sea-nettles, and sea-polypi. This last name has been peculiarly ascribed to them by the ancients, because of the number of feelers or feet of which they are all possessed, and with which they have a slow, progressive motion; but the moderns have given the name of polypus to a reptile that lives in fresh water, by no means so large or observable. These are found at the bottom of the wet ditches, or attached to the under surface of the broad-leaved plants that grow and swim on the waters. The same difference holds between these and the sea-water polypus as between all the productions of the sea and of the land and the ocean. The marine vegetables and animals grow to a monstrous size. The eel, the pike, or the bream of fresh waters is but small; but in the sea they grow to an enormous magnitude. The herbs of the field are at most but a few feet high; those of the sea often shoot forth a stalk of a hundred. It is so between the polypi of both elements. Those of the sea are found from two feet in length to three or four; and Pliny has even described one, the arms of which were no less than thirty feet long. Those in fresh waters, however, are comparatively minute, at their utmost size seldom above three parts of an inch long, and when gathered up into their usual form not above a third even of these dimensions.

It was upon these minute animals that the power of dissection was first tried in multiplying their numbers. They had been long considered as little worthy the attention of observers, and were consigued to that neglect in which thousands of minute species of insects remain to this very day. It is true, indeed, that Reaumur observed, classed, and named them. By contemplating their motions he was enabled distinctly to pronounce on their being of the animal and not of the vegetable kingdom; and then he called them polypi, from their great resemblance to those larger ones that were found in the ocean. Still, however, their properties were neglected and their history unknown.

Mr. Trembley was the person to whom we owe the first discovery of the amazing properties and powers of this little vivacious creature. He divided this class of animals into four different kinds-into those inclining to green, those of a brownish cast, those of a flesh-colour, and those which he calls the "polype de panache." The differences of structure in these as also of colour are observable enough; but the manner of their subsisting, of seizing their prey, and of their propagation, is nearly the same in all.

Whoever has looked with care into the bottom of a ditch when the water is stagnant and the sun has been powerful, may remember to have seen many little transparent lumps of jelly, about the size of a pea, and