III.519

WORMS.

Nearly all the animals of this, the lowest class of animal being, have but slow locomotive powers. Their bodies are soft, fleshy, and destitute of articulated members: some of them have hard internal parts, and others have crustaceous coverings. Many of them have arterial and veinous vessels, in which the blood undergoes a real circulation; but these are by no means common to the whole class. In some of them eyes and ears are very perceptible, while others seem to enjoy only the senses of taste and touch, which are never wanting. Many have no distinct head, and most of them are without feet. The whole of these creatures are very tenacious of life. In most of them parts that have been destroyed will afterward be reproduced.

They are divided into five orders⁕1:

1. Intestinal Worms. These are simple naked animals, without limbs, that live some of them within other animals, some in water, and a few in III.520 earth. The Ascarides, Tape-worms, Leeches, and Common Worms, are illustrations of this order.

2. Molluscous Worms. These are simple animals without shells, and furnished with tentacula or arms: most of them are inhabitants of the sea, and many possess a phosphorescent quality. The Sea Anemones, Cuttle-fish, Medusæ, Star-fish, and Sea-urchins, belong to the Molluscæ.

3. Testaceous Worms: are Molluscæ covered with calcareous shells, which they carry about with them; as the Muscles, Cockles, Oysters, Snails, &c.

4. Zoophytes: hold a rank between animals and vegetables, most of them taking root and growing up into stems and branches. Some of them are soft and naked, and others are covered with a hard shell.

5. Animalcules: are extremely minute, destitute of tentacula or feelers, and generally invisible to the naked eye. They are chiefly found in infusions of animal and vegetable substances of various kinds.

THE TAPE-WORMS, or TÆNIÆ⁕1.

Tæniæ are worms that inhabit the bodies of different animals, where they are destined to feed upon juices already animalized. They are generally found in the alimentary canal, and usually about the III.521 upper part of it, where there is the greatest abundance of chyle, which seems to be their natural food.

In structure they are very simple; for, being intended to be nourished by already digested food, they are not provided with complicated organs of digestion.

Their body is flat, and composed of numerous articulations; and the head has four orifices for suction a little below the mouth, which is terminal, and continued by a short tube into two ventral canals. The mouth is generally crowned with a double series of retractile hooks or holders.

We are not to suppose that these worms are created for the purpose of producing disease in the animals they inhabit, but rather that nature has directed that no situation should be vacant, where the work of multiplying the species of living beings could be carried on. By thus allowing them to exist within each other the sphere of increase is considerably enlarged. There is, however, little doubt that worms, and more especially those of the present tribe, do sometimes produce diseases in the bodies they inhabit: but we are at the same time very certain that worms do exist abundantly in many animals without at all disturbing their functions, or annoying them in the slightest degree: and we ought to consider all these creatures rather as the concomitants than the causes of disease.

The species of Tæniæ are not confined singly to particular animals: men are subject to several different species, and even the people of particular countries and climates are subject to particular III.522 species of them. The people of England have the Tænia Solium, or Common Tape-worm, and rarely any other: the inhabitants of Switzerland the Tænia lata, &c.

These creatures are apparently possessed of few senses. Nothing resembling brain or nerves has been discovered; but, as they are highly sensible to stimuli, it is most reasonable to conclude that they have a considerable portion of nervous matter in the composition of their bodies; that is, of such matter as is susceptible of stimuli. Indeed, we can scarcely conceive how any animal can even exist without such matter in its composition. Having no particular organs of sense, the touch is therefore the only evident source of intelligence which they possess.

The mode of increase or propagation of Tæniæ appears to be principally by ova; and there is reason to believe that these ova, as well as those of other intestinal worms, are so constructed as not to be easily destroyed. From this circumstance we may suppose them to pass along the circulating vessels of other animals. We cannot easily explain the phenomena of worms being found in the eggs of fowls, and in the intestines of a fœtus before birth, except by supposing their ova to have passed through the circulating vessels of the mother, and been by this means conveyed to the offspring⁕2.

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THE COMMON TAPE-WORM⁕.

The head of this animal is furnished with a mouth, and with an apparatus for giving it a fixed situation. The body is composed of a great number of distinct pieces articulated together, each joint having an organ by means of which it attaches itself to the inner coat of the intestine; and as these joints are sometimes exceedingly numerous, so of course will be the different points of attachment. The joints nearest the head are always small, and they become gradually enlarged as they are farther removed from it, except towards the tail, where a few of the last joints become again diminished. The body is terminated by a small semicircular joint, which has no opening.

The external parts are clothed with a fine membrane-like cuticle, immediately under which is a thin layer of fibres, lying parallel to each other, and running in the direction of the length of the animal’s body. In this direction all its motions are performed; from whence we may conclude that these fibres perform the office of muscles.

The head has a rounded opening at its extremity, which is considered to be the mouth. This opening is continued by a short duct into two canals, which pass round every joint of the animal’s body, and convey the aliment. The head is fixed to its place by means of two small tubercles, concave in the middle, that seem to serve the purpose of suckers. The III.524 alimentary canal passes along each side of the animal, sending a cross canal over the bottom of each joint, which connects the two lateral canals together. The internal structure of the joints is partly cellular and partly vascular: the substance itself is white, and in its texture somewhat resembles the coagulated lymph of the human blood.

The food of the Tæniæ, requiring probably very little change before it becomes a part of their body, is taken in at the mouth, and, being thrown into the alimentary canal, is made to visit, in a general way, every part. The central structure of the vessels placed in each joint seems calculated to absorb the fluid from the alimentary canal, for the purpose of sustaining and repairing the immediately adjacent parts: but there is in their bodies much cellular substance, into which no vessels enter. Such parts of the bodies of these animals are possibly nourished by transudation of the alimentary fluid into their cells; or this may be effected by the capillary attraction of their fibres. As they have no excretory ducts, the decayed parts of their bodies are most probably dissolved into a fluid which transudes through the skin like perspi­ration, and with this view the skin is extremely porous.

The length of the present Tænia is generally from three to thirty feet; but it has been known to reach sixty feet, and to be composed of several hundred joints.

When these worms produce a diseased state of body, those remedies (as drastic purges) are supposed to be the most effectual that operate partly III.525 by irritating the external surface of their bodies, so as to make them quit their hold, and partly by violent contractions in the intestines, which may sometimes divide their bodies, or even destroy them by bruising⁕1. Electrical shocks, passed frequently through the abdomen, it is supposed might be beneficial, as the lower orders of animals are in general easily destroyed by electrical shocks.

In injecting these Tæniæ with coloured size in order to preserve them, three feet in length from the head downwards has been filled by a single push with a small syringe; but the injection would not pass from below upward beyond the joint, owing, as it is supposed, to a valvular apparatus situated in the lateral canals immediately below the places where the cross canals are sent off⁕2.

THE THREAD-WORMS.

These troublesome animals are found in the bodies of some species of quadrupeds, birds, and insects. Most of the species perforate the skin immediately under which they lodge themselves; a few, however, have been discovered in the intestines. III.526 None of them have yet been found to infest the bodies of Reptiles or Fish.

Their body is round, thread-shaped, and very smooth. The mouth is dilated, and has a roundish concave lip.

THE INDIAN THREAD-WORM, OR GUINEA WORM⁕.

This species is too commonly found both in the East and West Indies. It enters the naked feet of the slaves, and occasions very troublesome itchings, and sometimes excites even fever and inflammation. It parti­cularly attacks the muscles of the arms and legs, from whence it is only to be extracted by means of a piece of silk or thread tied round its head. But the greatest caution is necessary in this simple operation, lest the animal, by being strained too much, should break; for, if any part remains under the skin, it grows with redoubled vigour, and becomes a cruel and sometimes a fatal enemy.

Dampier tells us that these worms are no thicker than a large brown thread, but, as he had been informed, five or six yards long. “If they break in drawing out, that part which remains in the flesh will putrefy, be very painful, and endanger the patient’s life, or at least the use of the limb; and I have known some that have been scarified and cut strangely to take out the worm.” He was unfortunate enough to have one of these creatures in III.527 his own ankle. “I was (he says) in great torments before it came out: my leg and ankle swelled, and looked very red and angry, and I kept a plaster to bring it to a head. At last, drawing off my plaster, out came about three inches of the worm, and my pain abated presently. Till then I was ignorant of my malady, and the gentlewoman at whose house I was took it for a nerve; but I knew enough what it was, and presently rolled it up on a small stick. After that I opened the place every morning and evening, and strained it out gently about two inches at a time, not without some pain, till at length I had got out about two feet.” He afterwards had it entirely destroyed by one of the negroes, who applied to it a kind of rough powder, not unlike tobacco-leaves dried and crumbled very small.

M. D’Obsonville received in his right leg the germ of one of these worms. He observed that its head was of a chesnut colour, and that to the naked eye it appeared to terminate in a small black point. On pressing it a little with a pin, and examining it with a common magnifying glass, he fancied he perceived something like a little trunk or tongue, capable of being pushed out or contracted. The body was not thicker than a strong thread; but, when the animal was extracted, it was found to be of the length of two or three ells. It appeared to be formed of a series of small rings, united to each other by an exceedingly fine membrane, and a single intestine extended through the body. It was extracted in the usual way; and the reason he gives for the injury done by breaking these animals is that they are full of a III.528 whitish acrimonious lymph, which immediately excites inflammation, and not unfrequently produces afterward an abscess or gangrene. The worm in his leg was twice broken, and twice occasioned an abscess. At last, at his own request, the part affected was rubbed with a preparation of mercury: and in eight or ten days the effect surpassed his hopes; for not only the body of the insect came away in suppuration, but the wound also, which was then more than three inches long, and considerably inflamed, was in this time almost entirely healed⁕1.

FURIA.

The body of the Furia is linear, and of equal thickness throughout. It has on each side a single row of close-pressed reflected prickles.

Of this tribe only one species, the Furia infernalis, has been hitherto discovered. In Finland, Bothnia, and the northern provinces of Sweden, the people were often seized with an acute pain, confined to a mere point, in the face, or other exposed part of the body, which afterwards increased to a most excruciating degree, and sometimes, even within a few hours after its commencement, proved fatal. This disorder was more particularly observed in Finland, especially about marshy places, and always in autumn. III.529 At length it was discovered that the pain instantly succeeded something that dropped out of the air, and almost in a moment penetrated and buried itself in the flesh. On more accurate attention, the Furia was detected as the cause. It is about half an inch in length, and of a carnation colour, often black at the apex. It creeps up the stalks of sedge-grass, and shrubs in the marshes, whence it is often carried off by the wind; and if the naked parts of the skin of any person happen to be directly in its course it immediately adheres, and buries itself within. The first sensation is said to be like that arising from the prick of a needle, this is succeeded by a violent itching of the part, soon after acute pain, a red spot and gangrene, at last an inflammatory fever, accompanied with swoonings. In the course of two days, at the farthest, death follows, unless the worm be extracted immediately, which is very difficult to be done. The Finlanders say, however, that a poultice of curds, or cheese, will allay the pain, and entice the animal out. Perhaps the most effectual method is carefully to dissect between the muscles where it had entered, and thus extract it with the knife.

Linnæus, as he was once collecting insects, was stung by the Furia in so dreadful a manner that there was great doubt whether he would recover.

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THE HAIR-WORMS.

These animals are inhabitants chiefly of stagnant waters. Their bodies are round, thread-shaped, equal throughout, and smooth.

THE COMMON HAIR-WORM⁕.

This worm is about the thickness of a horse’s hair, and, when full grown, is ten or twelve inches in length. Its skin is somewhat glossy, and of a pale yellowish white, except the head and tail, which are black. It is common in our fresh waters, and particularly in such where the bottom is composed of soft clay, through which it passes as a fish does through water⁕1.

Its popular name arose from the idea that it was produced from the hair of horses and other animals that were accidentally dropped into the water; an idea that is even yet prevalent among the lower class of the people, Its Linnean name of Gordius originated in the habit that it has of twisting itself into such peculiar contortions as to resemble a compli­cated gordian knot. In this state it often continues for a considerable time, and then slowly disengaging itself extends its body to the full length.

Sometimes it moves in the water with a tolerably quick undulating motion, like that of a leech; and III.531 at other times its motions are the most slow and languid imaginable. When the water in which it swims happens to be dried up, it soon loses every appearance of life; the slender body shrivels, and it may be kept in this state for a great length of time. But whenever it is put into water its body soon reassumes its former appearance; in less than half an hour it begins to move, and in a few minutes more it is as brisk and active as ever it was. The Abbé Fontana kept a Hair-worm in a drawer for three years, at the expiration of which it was perfectly dry and hard, and exhibited no signs of life; but, on putting it into water, it very soon recovered its former vigour. When kept in a vessel of water, it will sometimes appear motionless, and as if dead, for several hours, and afterward will resume its former vigour, and seem as healthy as before.

It is a very remarkable circumstance that its bite, which it sometimes inflicts on being taken out of the water, has been known to produce the complaint called a whitlow. This is mentioned by Linnæus as a popular opinion in Sweden, and it has since his time been confirmed by various other persons.

This Gordius is sometimes found in the earth as well as in water, and particularly in gardens of a clayey soil, after rain⁕2.

III.532

THE EARTH-WORMS.

The Earth-worms have a round annulated body, with generally an elevated fleshy belt near the head. Most of the species are rough, with minute concealed prickles placed longitudinally, and have in the body a lateral aperture or pore.

THE DEW-WORM⁕.

The most insignificant insects and reptiles are of much more conse­quence, and have much more influence in the economy of nature, than the incurious are aware of; and are mighty in their effect from their minuteness, which renders them less an object of attention, and from their numbers and fecundity. Dew-worms, though in appearance a small and despicable link in the chain of nature, yet, if lost, might make a lamentable chasm. For, to say nothing of half the birds and some quadrupeds that are supported by them, worms seem to be the great promoters of vegetation, which would proceed but ill without them, by boring, perforating, and loosening the soil, and rendering it pervious to rains and the fibres of plants, by drawing straws and stalks of leaves and twigs into it: and, most of all, by throwing up such infinite numbers of lumps called worm-casts, which form a fine manure for grain and grass.—Worms probably provide new soil for hills and III.533 slopes where the rain washes the earth away; and they affect slopes, probably to avoid being flooded.

Gardeners and farmers express their detestation of worms; the former, because they render their walks unsightly, and make them much work; and the latter, because they think worms eat their green corn. But these men would find that the earth without worms would soon become cold, hard-bound, and void of fermentation; and consequently sterile; and besides, in favour of worms, it should be hinted that green corn, plants, and flowers, are not so much injured by them as by many species of insects in their larva or grub state; and by unnoticed myriads of those small shell-less snails, called slugs, which silently and imperceptibly make amazing havoc in the field and garden.

Lands that are subject to frequent inundations are always poor: one great reason of this may probably be because all the worms are drowned.

The Dew-worm is without bones, without brain, eyes, and feet. It has a number of breathing-holes along its back, adjoining to each ring. Near its head is placed the heart, which may be observed to beat with a very distinct motion. The body is formed of small rings furnished with a set of muscles that act in a spiral direction, and which enable it in the most complete manner possible to penetrate into or creep upon the earth. The motion of these creatures may be explained by a wire wound on a cylinder; where, when one end is drawn on and held fast, the other, upon being loosed, will immediately follow. These muscles enable them with great III.534 strength to dilate or contract their bodies. The annuli or rings are also each armed with small, stiff, and sharp beards, or prickles; which they have the power of opening out or closing to their body. And under the skin is secreted a slimy matter, which they emit at the perfo­rations between the annuli to lubricate the body, and facilitate their passage into the ground. By all which means they are enabled with great ease to perforate the earth; which, had their bodies been otherwise constructed, they could not so well have done.

Dew-worms make their casts principally about the months of March or April, in mild weather.—In rainy nights they travel about, as appears from their sinuous tracks, on a soft muddy soil, perhaps in search of food. When they appear at night on the turf, although they considerably extend their bodies, they do not quite leave their holes, but keep their tails firmly fixed, so that, on the least alarm, they can precipitately retire under the earth. Whatever food falls within their reach, when thus extended, such as blades of grass, or fallen leaves, they seem content with it.

Helpless as they may seem, these creatures are very vigilant in avoiding such animals as prey upon them. The mole, in particular, they avoid by darting to the surface of the earth the instant they feel the ground move. Fishermen, who are acquainted with this circumstance, can take them in great numbers, by moving the earth in places where they expect to find them, with a dung fork. When, however, they are wanted for fishing, they are perhaps III.535 most easily caught by the light of a lantern in the night, after heavy showers, on grass walks and sheep pastures, where the herbage is short.

In winter these worms retire very deep into the earth, to secure themselves from being frozen. They do not become torpid during this season, for in the intervals of mild weather they are often observed to throw up their casts, as usual at other times of the year.

THE LEECHES.

The body of the Leech is oblong and truncate, or as if cut off at both ends. These animals are cartilaginous, and move by dilating the head and tail, and contracting themselves into the form of an arch.

Some species are viviparous, others lay their eggs on aquatic plants, and others carry them under their belly. Each egg contains many young ones. Several of the smaller species may be multiplied by cutting.

THE MEDICINAL LEECH⁕

Is usually found in stagnant ponds and ditches, and is of an olive black colour, with six yellowish lines above, and spotted with yellow beneath. It III.536 is generally two or three inches in length. The body is formed with numerous annular wrinkles, which the animal has the power of expanding or contracting at pleasure. The tail ends in a circular muscle or sucker, which, when applied to any substance, readily adheres, by the animal’s drawing up the middle, so as to have it pressed firmly down by the external air. By this it fastens itself with ease and security, while it extends the other part of the body in any direction; and it is so firmly fixed that it can move its head about to seek for nourishment, without any danger of being carried away by the strength of the current. When the Leech is desirous of moving onward, it extends its body forward, fixes its head in the same manner that it did its tail, and then loosens and draws that up, and again fastens it near its head as a fresh point to proceed from.

The head of the Leech is armed with three teeth of a slightly cartilaginous substance, which are so situated as to converge when the animal bites, and leave a somewhat triangular mark on the skin. These are sufficiently strong to pierce the skin of an ox or a horse. Through the holes it forms with them it sucks the blood: this is done by contracting the muscles of the throat so as to make the blood rush through the vacuum above the wound into the stomach, which is a kind of membranaceous receptacle divided into twenty-four small cells. Here it sometimes remains for several months almost without coagulating, and affords support to the animal during the whole time. It passes off by transpiration, III.537 the matter fixing on the surface of the body, and afterward coming off in small threads. In proof of this, if a leech be immersed in oil (where it will keep alive for several days) and afterward put into water, a kind of slough will be seen to loosen from its skin, exactly of the shape of the body.

The Leech is a viviparous animal, producing one young at a time, and this about the month of July. If it be confined in a glass, and kept in a room, it is said to shew itself very restless before a change of weather.

When it is applied in surgery, and is found to adhere too long, it is easily removed by putting upon it salt, pepper, or acids.

THE SLUG TRIBE⁕1.

The body of the Slug, or naked Snail, is oblong, and has on its upper part a kind of fleshy shield; and below a flat longitudinal disk, by means of which the animal has its progressive motion. On the right side of the body there is an aperture. Above the mouth are situated four feelers, at the apex of each of the two larger of which there is an eye.

Few animals, for their size, are more voracious than these. They would do serious injury to our III.538 fields and gardens were not their numbers abridged by several of the smaller quadrupeds, and by various species of birds.

They have so strong a tendency to reproduction that, if the head or tail be cut off, these parts will grow again. Most of the species can exist for a great length of time, several months, without food.

THE SPINNING SLUG⁕.

About the year 1789, Mr. Hoy observed, in a plantation of Scotch firs, something hanging from one of the branches, which, as it seemed uncommon, he approached, and found to be this animal. It was hanging by a single line or thread attached to its tail. This was, upward, very fine; but near the animal it became thicker and more broad, till at length it exactly corresponded with the tail. The slug was about four feet below the branch, and nearly at the same distance from the ground; which it gradually approached at the rate of an inch in about three minutes⁕1. This rate, though slow, is not so much so as might be expected, consi­dering that the animal is not furnished with any peculiar receptacle, as in some insects, for the glutinous liquid from which its silken lines are formed. The line by which it descended was drawn from the slimy exudation gradually secreted from the III.539 pores that covered its whole body. A great degree of exertion seemed necessary to produce a sufficient supply of the liquid, and to force this toward the tail. It alternately pushed out and drew back its head; and turned it as far as possible, first to one side and then to the other, as if thereby to press its sides, and thus promote secretion. This motion of the head in an horizontal direction made the whole body turn round; by which the line, which would have otherwise remained somewhat flat, became round. This motion also, no doubt, in addition to the weight of the animal, tended materially toward lengthening the line⁕2.

This is the substance of Mr. Hoy’s account. Dr. Latham says that the secretion from which the thread is formed is wholly from the under parts of the animal, and not from the back or sides, both of which, during the operation, appear nearly dry. That it did not proceed from any orifice in the tail was evident; for in some experi­ments the animal was suspended by the tip, and at other times from the side, a full eighth of an inch from the tip. The flow of the viscous secretion toward the tail appeared to be excited by means of an undulating motion of the belly, similar to that of crawling.

After having spun for some time, the power of spinning seems for a while to be lost: but in those slugs on which experi­ments have been made it has always been recovered, after their being kept some hours among wet moss⁕3.

III.540

This slug is of a greyish white colour, with a yellowish shield, and is generally about three fourths of an inch in length. It is supposed not to be very uncommon in woods and other shady places.

THE NEREIS TRIBE.

The animals of this tribe are long and slender. Their feet are very numerous, and arranged on each side of the body. They have, in general, two or four eyes, but some of the species have none. Their feelers are simple, and placed above the mouth.

THE NIGHT-SHINING NEREIS⁕.

The body of this little creature is oblong, linear, and so minute as to elude examination by the naked eye. It inhabits every sea, and is one of the causes of the luminous shining of the water in the night, which is sometimes so great as to make that element appear as if on fire. The body, composed of about twenty-three segments or joints, is altogether scarcely two lines long, quite pellucid, and its colour that of water green.

These animals are found on all kinds of marine plants; but they often leave them, and swim on the surface of the water. They are frequent at all seasons, III.541 but particularly in summer before stormy weather, when they are more agitated and more luminous than at other times. Their numbers, and wonderful agility, added to their pellucid and shining quality, do not a little contribute to their illuminating the sea; for myriads of these animalcules may be contained in a small cup of sea-water. Innumerable quantities of them lodge in the cavities of the scales of fishes, and to them probably the fish may in some measure become luminous. “I have observed with great attention (says Barbut) a fish just caught out of the sea, whose body was almost covered with them, and have examined them in the dark: they twist and curl themselves with amazing agility, but soon retire out of our contracted sight; probably on account of their glittering numbers dazzling the eye, and their extreme minuteness eluding our researches. It is to be observed that, when the unctuous moisture which covers the scales of fishes is exhausted by the air, these animals are not to be seen; nor are the fishes then noctilucous, that matter being perhaps their nourishment when living, as they themselves afford food to many marine animals. They do not shine in the daytime, because the solar rays are too powerful for their light, however aggregate, or however immense their number⁕1.”

Their appearance is particularly brilliant when the wind is in the east and south-east points, and in winter nights preceded by a warm day. If water III.542 containing these animalcules be kept warm, they will retain their light two whole days after they are dead; but in cold weather they lose it in the course of seven or eight hours. Motion and warmth, which increase their vivacity and strength, increase also their light.

THE ACTINIÆ, OR SEA ANEMONES.

These animals are somewhat oblong, and when closed resemble a truncated cone. They are fixed by the base, and from their top occasionally extend several tentacula, which are disposed in regular circles. The mouth, which is the only opening in the body, is situated at the top, in the centre of the tentacula, and is furnished with crooked teeth.

They are all capable of varying their figure: but, when their tentacula are fully expanded, they have the appearance of full-blown flowers. Many of them are of very beautiful and brilliant colours. They feed on shell-fish and other marine animals, which they draw into their mouth with their arms; and they eject the shells and other indigestible parts through the same opening. It sometimes happens, however, that a shell presents itself in a wrong position, and the animal is not able to discharge it in the usual manner: in this case we are told that it is forced through the body, making a wound, as if with a knife, near the base. The arms seem to lay hold of objects by making a vacuum; for, on touching III.543 them with the fingers, they readily adhere, but no viscous matter is deposited by them. Their mouth is capable of great extension, so as to allow them to swallow very large shells without injury. The whole interior part of their body is one cavity or stomach. They have the power of progressive motion; but this is extremely slow, and is said to be performed by loosing their base from the rock, reversing their body, and employing their tentacula as so many legs.

Nearly all the animals of this tribe may be separated from their native rocks by means of a card carefully introduced beneath, so as not materially to injure them; and, being put into glass vessels with sea-water, which must be changed about once a week, they will there fix themselves, and may be kept alive and in full vigour for a great length of time, in places far distant from the sea-coasts.

All the species are viviparous.

THE COMMON SEA ANEMONE⁕.

The present species is extremely common on several of the European coasts, and on the sea rocks of this island in particular. It adheres by its base firmly to the rocks, so as frequently to be left above water at the ebbing of the sea: but it is generally found adhering at some little depth below the surface of the water. Its usual colour is a deep red, more or less vivid in different specimens; and it is III.544 of nearly the same height when closed. Its form is that of a very obtuse cone, with an orifice at the top, which it can at pleasure either close entirely or extend very wide, to admit its tentacula to spread out, and to receive such food as they draw into it. These tentacula are varied with red in such manner as, when fully expanded, to bear a very considerable resemblance to the flower of some of the garden Anemones. If any extraneous substance is intro­duced into the cavity of the mouth, or even if any of the tentacula are but slightly touched, the animal instantly contracts itself into a conoid shape.

THE PURPLE SEA ANEMONE⁕.

On this species the abbé Dicquemaire made several experi­ments to prove its powers of reproduction, &c. He first cut off all its tentacula, which grew again in less than a month; and, on repeating this a second and third time, he had equal success. One of the animals had its upper part cut off: the base was found, a few days afterward, to have fallen from its place, but it soon entirely recovered its limbs. After cutting one of them in two, the abbé offered a piece of a muscle to the detached part, and the limbs seemed eager to take it. They drew it into the mouth, and it was swallowed; but, as the body was wanting to receive it, the piece came out at the opposite end, “just (says the abbé) III.545 as a man’s head, being cut off, would let out at the neck the bit taken in at the mouth.” It was offered a second time and again received, and retained till the following day, when it was thrown up. In this manner it was fed for some time, the bits, when they did not pass through, appearing considerably altered on their re-appearance at the mouth.—If the base of any of the Anemones be injured by the incision, the wound generally proves mortal.

On being put under the receiver of an air pump, and having the air exhausted, these animals did not seem to experience any ill effects, or to perceive any difference betwixt this and their being in the open air: if their tentacula happened to be expanded they remained so, and not the least shrinking could be perceived.

Some of them lived upwards of twelve months without any other food than what the sea-water afforded them.

When shell-fish, or pieces of other fish, or bits of raw meat, were offered, if not too large, they always took them. The shells, even if closed, they ejected in the course of a day or two, but perfectly cleared of their contents.

They bring forth their young alive at the mouth; and the abbé had these produced several times in his hands: they were generally from eight to twelve in number. Though some of them are at this time almost imperceptible, yet they immediately fix themselves, III.546 and expand their tentacula in order to catch their prey.

These animals are destitute of eyes, yet they were always very evidently affected by light. If a candle was held over the glasses in which they were kept, and at such a distance as not to communicate any heat, they regularly closed, and did not again expand till the light was removed. When, however, they had been plentifully fed, they closed much slower, or sometimes even remained open.

When the Sea Anemones are boiled in water they acquire a firm consistence, and become a very palatable food. Cats are remarkably fond of them when thus cooked. Their smell is not unlike that of a warm crab or lobster.

Among other experiments of the abbé Dicquemaire, he gave to two Actiniæ of different species (a grey and a yellow one) a narrow slice of fish, so laid that each had hold of an end. The yellow one, however, happened to seize the larger share. Each swallowed on by its respective end, till at length their mouths came in contact. The grey one seemed at first to get the better; but the other soon recovered its share, lost it again, and again recovered it. These alternate victories lasted about three hours, till at last, the grey one losing its hold, the other obtained the prize. This sucked it in but slowly, and the grey one again ventured its mouth upon a last tug at the end still within reach: but the effort proved fruitless; the yellow companion gave a final pull, and swallowed the whole. During this contention, both the creatures seemed animated by considerable III.547 passion; but, though they remained neighbours for a great while afterward, they lived together very peaceably⁕1.

THE SEA-MARIGOLD⁕.

Mr. Hughes, in his Natural History of Barbadoes, has given us a very minute account of this species, several individuals of which were discovered in that island some years ago. He calls it an animal flower, and seems to consider it as a sensitive plant, having many animal properties.

“The cave that contained these animals was (he says) near the bottom of a rocky cliff facing the sea, in the north part of the island, in the parish of St. Lucy. The descent to it was steep and dangerous, being in some places almost perpendicular. The cave contained a natural bason of water, about sixteen feet long and twelve broad, in the middle of which was a rock almost covered with them.

“Round the sides of this, at different depths under the water, seldom however more than eighteen inches, were seen at all times of the year seemingly fine radiated flowers of a pale yellow, or a bright straw-colour, slightly tinged with green.—These had the appearance of a circular border of thick-set petals, about the size of and much resem­bling those of the single garden marigold.

“I often attempted to pluck one of them from the rock to which they are fixed, but could III.548 never effect it. For as soon as my fingers came within two or three inches of it, it would immediately contract and close together its yellow border, and shrink back into the hole in the rock; but, if left undisturbed for three or four minutes, it would come again gradually into sight, expanding, though at first very cautiously, what seemed its leaves, till at last it appeared in its former bloom: it would, however, again contract, with surprising quickness, when my hand approached within a little distance of it.” This gentleman also attempted to touch it with his cane, and then with a slender rod; but the effect was the same. The motion of the water, caused by the immersion of the hand or stick, was no doubt the cause of its invariably retreating when any attempt was made to touch it.

From the centre of the apparent flower proceeded four dark-coloured threads, somewhat resembling, says Mr. H., the legs of a spider. These, which were its arms or feelers, had a quick spontaneous motion from side to side.

Its body seemed to be a small dark coloured tube, about as thick as a raven’s quill, one end of which was affixed to the rock, and the other, which extended a little way from it, was encircled with the yellow border above mentioned.

Soon after the discovery of these surprising animals, great numbers of people came to see them. This was attended with some inconvenience to the person through whose grounds they were obliged to pass, and he resolved to destroy the objects of their curiosity. That this might be done effectually, he caused III.549 all the holes, out of which the animals appeared, to be carefully drilled with an iron instrument. He could not, however, even by this means destroy them; for in the course of a few weeks they again appeared in the very same places, and in a short time became as numerous as before.

THE CUTTLE-FISH TRIBE.

The Cuttle-fish, though comparatively large animals, some of them being two feet long and upward, are ranked by Linnæus under the class of Worms.—Their structure is very remarkable. The body is cylindrical, and, in some of the species, entirely covered with a fleshy sheath; in others, the sheath reaches only to the middle of the body. They have eight tentacula, or arms, besides two feelers, as they are called, which are much longer than the arms. Both the feelers and arms are furnished with strong circular cups or suckers, by means of which the animal seizes its prey, and firmly attaches itself to rocks or other hard substances. To do this it applies their surface, extended and plain, to the surface of the body, and then drawing them up in the centre by muscles contrived for the purpose, a vacuum is formed, and they adhere by the pressure of the external air.—The adhesive power is so great that it is generally more easy to tear off the arms than separate them from the substance to which they are fixed. If these III.550 arms happen by any chance to be broken off they are soon afterward reproduced. The animals are also furnished with a hard strong and horny mouth, resembling, both in texture and substance, the beak of a parrot. With this they are enabled to break the shells of Limpets, and other shelled animals, on which they feed. In the back, under the skin, there is a kind of bone composed of thin parallel plates, one above another, and separated by little columns arranged in quincunx order. This bone is oval, thick toward the middle, and thin at the circumference. It is extremely light, and generally elastic, and in the living animal transparent like glass: the surface, in some species, is marked with longitudinal furrows. When dried and pulverised, the bone of the Officinal Cuttle-fish is employed by silversmiths for moulds, in which they cast their small work, as spoons, rings, &c. It is also converted into that useful article of stationary called pounce. This bone, on account of its lightness, is sometimes called sea-foam, or sea-biscuit.

In the belly of the Cuttle-fish there is a vessel that contains a quantity of dark or inky fluid, which the animal emits, on contraction, when alarmed. This not only tinges the water so as to conceal its retreat, but is at the same time so bitter as immediately to drive off its enemies.

Swammerdam was of opinion that Indian ink is nothing more than this black fluid in an inspissated state, with the addition of perfumes. If Indian ink be dissolved in water in any considerable quantity, in the space of a few days it acquires a very high degree of putridity, clearly indicating its being formed of some animal substance; and no other seems so well calculated to compose it as this.

The male always accompanies the female, and when she is attacked will brave every danger, and attempt her rescue even at the hazard of his own life. As soon as she observes her partner to be wounded she immediately escapes, her timidity not suffering her to afford him any assistance. When these animals are dragged out of the water, they make a noise somewhat like the grunting of a hog.

The young are produced from eggs deposited on the sea-weed, in parcels exactly resembling a bunch of grapes. These are at first white, but after their impregnation by the male they become black: they are round, with a little point at the end, and in each of them is contained a Cuttle-fish surrounded by a gelatinous fluid.

The Officinal Cuttle-fish⁕2 was in great esteem by III.552 the ancients as food, and it is even yet used as such by the Italians.

The Eight-armed Cuttle-fish⁕3 in the hot climates sometimes becomes of such a size as to measure twelve feet across its centre, and to have each of its arms between forty and fifty feet long. When the Indians go out in their canoes, in places frequented by these Sepia, they are always in dread of their flinging their arms over and sinking them; on which account they are careful to take with them an ax to cut them off.

THE STAR-FISH, or SEA-STAR.

These are inhabitants of the sea, and are usually found on the sand or among the rocks on the sea-shore, considerably below high-water mark. Their covering is a coriaceous crust, which defends them from the attacks of the smaller animals; and they have five or more rays proceeding from a centre in which their mouth is situated. Every ray is furnished with a prodigious number of tentacula, or short soft and fleshy tubes, which appear to be of use not only in taking prey, and in aiding the motion of the animal, but also in enabling it to adhere to rocks and other substances, by which it withstands the force of the waves. In a single animal these tentacula have III.553 been found above 1500 in number: and, when the Star-fish are thrown on their backs, these may be observed to be pushed out and withdrawn in the same manner as snails do their horns. The progressive motion of the Star-fish, which is with their rays, is very slow: and by the undulation of these they are enabled to swim. They possess considerable powers of reproduction: for if, by any violence, a ray is broken off, for most of them are very brittle, in the course of a short time a new one will appear. The mouth is armed with bony teeth, that are used in seizing and breaking the shells an which the animals feed: from hence a canal extends to each of the rays, runs through the whole length, and becomes gradually narrower as it approaches the extremity.

If the Star-fish are drowned in brandy or spirits of wine, and the rays be kept flat and expanded during the time, it is easy afterward to extract, by means of a pair of forceps, the stomach and intestines entire through the mouth. This information may be of use to those who wish to preserve specimens of them, and were not previously possessed of it.

THE ARBORESCENT STAR-FISH⁕.

This extremely singular species is occasionally found in most seas, but never in any great number. It has five equi-distant, thickly jointed processes proceeding from its centre, each of which is divided into two other small ones, and each of these into two III.554 others still smaller; and this mode of regular subdivision is continued to a vast extent, and in the most beautiful gradation of minuteness, till at length the number of extreme ramifications sometimes amount to several thousands. One specimen, that measured three feet across, had five hundred and twelve extremities to each ray; so that, in this, the whole number was 2560. By this most curious structure the animal becomes as it were a living net, and is capable of catching such creatures as are by nature destined for its prey, by the sudden contraction of its innumerable ramifications; and the unfortunate object is secured by these beyond all possibility of escape⁕1.

In order to preserve this curious animal whole and undamaged for cabinets, it should be taken far out in the sea; and the fishermen ought to be careful not to break off any of the limbs, and to prevent the animal from contracting and entangling its outer and most slender branches. The fishermen of the Cape of Good Hope get six, and sometimes even ten, rix-dollars for one of these Star-fish.

When it is alive, or but just dead, its colour is a reddish or deep carnation; but on being dried it becomes somewhat grey. It should be dried in the shade, in some open place, where the wind has free access to it; for in the sun it is apt to dissolve, and if placed too much in the shade it frequently becomes putrid⁕2.

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THE SEA-URCHINS⁕1.

The Sea-urchins are generally round, and shaped like a somewhat flattened ball. Their exterior is a bony crust, usually furnished with moveable spines, by which they are defended from injury, and by means of which they have their progressive motion: these are often very numerous, amounting in some species to upwards of two thousand. The mouth is placed beneath, and in most of the species has five valves or teeth.

They are all inhabitants of the sea, and, in their general character, have so great an alliance to each other that it will not be necessary to bring forward more than one species, to illustrate the whole tribe.

THE COMMON SEA-URCHIN⁕.

This animal, which lodges in cavities of rocks just within low-water mark, on most of the British coasts, is nearly of a globular shape, having its shell marked into ten partitions or divisions, not much unlike those of an orange. The mouth is situated in the lower or under part, and armed with five strong and sharpened teeth. The stomach and intestines, which are of considerable length, are disposed in a somewhat circular III.556 form; and the whole body is supported entirely by a set of upright bones or columns. On the outside of the shell is a prodigious number of sharp moveable spines, of a dull violet and greenish colour, curiously articulated, like ball or socket, with tubercles on the surface, and connected by strong ligaments to the skin or epidermis with which the shell is covered. The spines are the instruments by which the animal conveys itself at pleasure from one place to another; and by means of these it is enabled to move at the bottom of the water with great swiftness. It generally employs those about the mouth for this purpose, keeping that opening downward; but it is also asserted to have the power of moving forward by turning on itself like a wheel⁕1. When any thing alarms these animals, they immediately move all their spines toward it, and wait an attack, as an army of pikemen would with their weapons. The number of muscles, fibres, and other apparatus necessary to the proper management of these must be very great, and are exceedingly wonderful. So tenacious are the Sea-urchins of the vital principle that, on opening one of them, it is no uncommon circumstance to observe the several parts of the broken shell move off in different directions. The ancients, according to Oppian, gave credence to a circumstance much more wonderful than this.

Between the spines, and disposed in a continued longitudinal series on the several divisions or regions of the shell, are an infinite number of very small foramina, communicating with an equal number of tentacula placed above them. These are the instruments by which the creature affixes itself to any object, and stops its motions. They are possessed of a very high degree of contractile power, and are furnished at the extremities with an expansile part, which may be supposed to operate as a sphincter, or as the tail of a leech, in fastening the animals securely to rocks and other substances to which they chuse to adhere.

The shell of this animal, when deprived of the spines, which often fall off after its death, is of a pale reddish tinge, and the tubercles on which the spines are fixed appear like so many pearly protuberances on the surface.

At Marseilles, and in some other towns on the continent, this species is exposed for sale in the markets as oysters are with us, and is eaten boiled like an egg. It forms an article of food among the lower class of people on the sea-coasts of many parts of III.558 this country, but does not seem to have made its way to the tables of the opulent. The Romans adopted it, and dressed it with vinegar, mead, parsley, and mint⁕2.

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THE BERNACLES⁕1.

These shells are fixed at the base, and consist of more than two unequal and erect valves. The animal that inhabits them is similar to one inhabiting submarine rocks, that Linnæus has placed in the last order, under the name of Triton.

The two shells of this tribe that are best known are the Common Bernacle⁕2, which is found adhering in vast numbers to rocks, and to oysters and other shell-fish; and the Goose-Bernacle⁕3, so well known from the fables of its producing the Bernacle Goose.

The animals contained in these shells as well as in those of all the other species, have twenty-four claws or tentacula, all joined in pairs near the bottom, and inserted in one common base. The twelve longest stand somewhat erect and arched, arising from the back part of the animal; they appear like so many yellow curled feathers, clear, horny and articulated: every joint is furnished with two rows of hairs on the concave side. They are of use in catching prey, and the animals are continually extending and contracting these arched hairy claws, which serve as a net.

The twelve smallest are placed, six on each side, in the front of these. They are more pliable and III.560 more thickly set with hairs than the others, and seem to perform the office of hands.

The trunk or proboscis rises from the middle of the base of the larger claws, and is longer than any of them. This the animal moves with great agility in any direction; it is tubular, transparent, and composed of rings lessening gradually to the extremity, where it is surrounded with a circle of small bristles, which are likewise moveable. Along the inside of this transparent proboscis appears the spiral dark-coloured tongue, which is extended and contracted at pleasure.

The mouth, formed not unlike a contracted purse, is placed in front between the smaller claws, within the folds of which are six or eight horny laminæ or erect teeth. Under this lie the stomach, intestines, and tendons, by which the animal adheres to the shell⁕4.

The Goose Bernacles consist each of five shells. They adhere in clusters to the bottoms of vessels and old timber, by means of tubes that in appearance are like some of the Corallines⁕5.

THE PHOLAS TRIBE.

The Pholas has a shell of two valves, that open widely at each end, with several lesser ones at the III.561 hinge. The hinges are folded back, and united by a cartilage; and in the inside, beneath the hinge, there is an incurved tooth. The animal contained in this shell is called an Ascidia.

The animals of this tribe perforate clay, spongy stones, and wood, while very young; and, as they increase in size, they enlarge their habitation within, and thus become imprisoned. They are always found below high water-mark, and a mass of rock may sometimes be seen wholly perforated by them. They have two orifices or openings capable of elongation in the manner of a proboscis: one of these is supposed to be the mouth, and has the faculty of spouting water. Most of them contain a phosphorescent liquor, of great brilliancy in the dark, which also illuminates whatever it touches or happens to fall upon.

From the following species the character of nearly the whole tribe may be collected.

THE DACTYLE PHOLAS⁕.

This is an oblong shell, marked with somewhat spinous stripes. When full grown, it is about an inch and a quarter long, and near five inches broad. It is of a whitish colour, and, in external appearance, has a distant resemblance to a Muscle.

The great powers of penetration of these animals, compared with their apparent imbecility, have justly excited the astonishment of philosophers and naturalists III.562 in all ages. When divested of their shell they are roundish and soft, with no instrument that seems in the least fitted for boring into stones, which they are known to do, or even for penetrating the softest substance. They are, indeed, each furnished with two teeth; but these are placed in such a situation as to be incapable of touching the hollow surface of their stony dwellings. They have also two corners to their shells, that open and shut at either end; but these are totally unserviceable to them as miners. The instrument with which they perform all their operations, and by means of which they bury themselves in the hardest rocks, is only a broad fleshy substance, somewhat resembling a tongue, that is seen issuing from the bottom of the shell. With this soft yielding instrument, while yet young and small, they work their way into the substance of the stone, and they enlarge their apartment as their increasing size renders it necessary.

The seeming unfitness, however, of this animal for penetrating into rocks, and there forming a habitation, has induced many philosophers to suppose that they entered the rock while it was yet in a soft state, and, from the petrifying quality of the water, that the whole rock afterward hardened round them by degrees. This opinion, however, has been confuted, in a very satisfactory manner, by Dr. Bohads, who observed that many of the pillars of the temple of Serapis at Puteoli were penetrated by these animals. Whence he justly concludes that the Pholades must have pierced into them after III.563 they were erected; for no workman would have laboured a pillar into form, if it had been honey-combed by worms in the quarry. In short, there can be no doubt but that the pillars were perfectly sound when erected, and that these animals attacked them during the time in which they continued buried under water, from the earthquake that swallowed up the city.

From hence it appears that, in all nature, there is not a greater instance of perseverance and patience than what this animal is seen to exhibit. Furnished with the bluntest and softest augre, by slow successive applications, it effects what other animals are incapable of performing by force, penetrating the hardest bodies only with its tongue. When, while yet very small, it has effected an entrance and buried its body in the stone, it there continues for life at its ease; the sea-water that enters at the little aperture supplying it with luxurious plenty. Upon this seemingly thin diet it by degrees grows larger and larger, and soon finds itself under the necessity of increasing the dimensions of its habitation and its shell.

The motion of the Pholas is slow beyond conception; its progress keeps pace with the growth of its body; and, in proportion as it becomes larger, it makes its way farther into the rock. When it has got a certain way in, it then turns from its former direction and hollows downward; till, at last, when its habitation is completed, the whole apartment resembles the bowl of a tobacco-pipe; the hole in the shank being that by which the animal entered.

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Thus immured, the Pholas lives in darkness, indolence, and plenty; it never removes from the narrow mansion into which it has penetrated; and seems perfectly content with being inclosed in its own sepulchre. The influx of the sea-water that enters by its little gallery satisfies all its wants; and, without any other food, it is found to grow from five to eight inches long, and thick in proportion.

Yet the Pholas, thus shut up, is not so solitary an animal as would at first appear; for though it is immured in its hole, without egress, though it is impossible for the animal, grown to a great size, to get out by the way it made to get in, yet many of this kind often meet in the heart of the rock; and, like miners in a siege (who sometimes cross each other’s galleries), they frequently break in upon each other’s retreats. They are commonly found in great numbers in the same rock, and sometimes above twenty are discovered within a few inches of each other.

This animal is found in the greatest quantity at Ancona, in Italy; it is found also along the shores of Normandy and Poitou, in France, and upon some of the coasts of Scotland. It is in general considered as a very great delicacy at the tables of the luxurious⁕1.

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THE RAZOR-SHELLS⁕1.

These shells are bivalve, oblong, in shape somewhat resembling the handle of a razor, and open at both ends. The hinge has a small and sharp reflected tooth, sometimes double, not inserted into the opposite valve. The animal is similar to that of the last tribe.

Many of the bivalved shell-fishes have the power of performing a progressive or retrograde motion, by an instrument that has some resemblance to a leg or foot, and called the tongue. But the present animals can, at pleasure, make this assume almost every kind of form, as their exigences require. By this tongue they are not only enabled to creep, to sink into the mud, or disengage themselves from it, but to perform a motion which no one could suppose shell-fishes were capable of performing.

All the species of Razor-shells are incapable of progressive motion on the surface; but they dig a hole or cell in the sand, sometimes two feet in depth, in which they can ascend or descend at pleasure. The instrument or tongue, by which they perform all their motions, is situated at the centre. It is fleshy, cylindrical, and tolerably long. When necessary, the animals can make the termination of III.566 the tongue assume the form of a ball. The Razor-fish, when lying on the surface of the sand, and about to sink into it, extends its tongue from the inferior end of the shell, and makes the extremity of it take the form of a shovel, sharp on each side, and terminating in a point. With this instrument the animal cuts a hole in the sand. After the hole is made, it advances the tongue still farther into the sand, makes it assume the form of a hook, and with this hook, as a fulcrum, it obliges the shell to descend into the hole. In this manner the animal operates till the shell totally disappears. When it chuses to regain the surface, it puts the termination of the tongue into the shape of a ball, and makes an effort to extend the whole tongue: but the ball prevents any farther descent, and the muscular effort necessarily pushes the shell upward till it reaches the surface, or top of the hole. It is amazing with what dexterity and quickness these seemingly awkward motions are performed.

It is remarkable that the razor-fish, though it lives in salt water, abhors salt. When a little salt is thrown into the hole, the animal instantly quits his habitation. But it is still more remarkable that, if the animal is once seized with the hand, and afterwards allowed to retire into its cell, salt will then be strewed in vain, for the fish will never again make its appearance. If it be not handled, by applying salt, the animal may be made to come to the surface as often as a person pleases; and fishermen often make use of this stratagem. This conduct III.567 indicates more recollection than one would have been inclined to expect from an animal so low in the order of nature as a Razor-fish.

THE OYSTER TRIBE.

The Oysters are bivalve shell-fish, having the valves generally unequal. The hinge is without teeth, but furnished with a somewhat oval cavity, and mostly with lateral transverse grooves.

From a similarity in the structure of the hinge, the Oysters and Scallops have been united into one tribe. But they differ very essentially, both in their habits, and in their external appearance. The Oysters adhere to rocks, or, as in two or three species, to roots of trees on the shore; while the Scallops are always detached, and usually lurk in the sand.

THE EDIBLE OYSTER⁕.

These Oysters inhabit the European and Indian seas, and are well known as a palatable and nutritious food. Most of our coasts produce them in great abundance, but the coasts chiefly celebrated are those of Essex and Suffolk. Here they are dredged up by means of a net, with an iron scraper at the mouth, that is dragged by a rope from a boat, III.568 over the beds. As soon as taken from their native beds they are stored in pits formed for the purpose, furnished with sluices; through which, at the spring tides, the water is suffered to flow. This water, being stagnant, soon becomes green in warm weather, and, in a few days afterward, the Oysters acquire the same tinge, which renders them of greater value in the market: but they do not acquire their full quality, and become fit for sale, till the end of six or eight weeks.

The principal breeding-time of Oysters is in April and May, when they cast their spawn, or spats, as the fishermen call them, upon rocks, stones, shells, or any other hard substance that happens to be near the place where they lie, to which the spats immediately adhere. These, till they obtain their film or crust are somewhat like a drop of a candle, but are of a greenish hue. The substances to which they adhere, of whatever nature, are called cultch. From the spawning-time till about the end of July the Oysters are said to be sick, but by the end of August they become perfectly recovered. During these months they are out of season, and are bad eating. This is known, on inspection, by the male having a black and the female a milky substance in the gill.

The Oyster fishery of our principal coasts is regulated by a court of admiralty. In the month of May the fishermen are allowed to take the Oysters, in order to separate the spawn from the cultch, the latter of which is thrown in again to preserve the bed for the future. After this month it is felony to carry III.569 away the cultch, and otherwise punishable to take any Oyster, between whose shells, when closed, a shilling will rattle. The reason of the heavy penalty on destroying the cultch is that, when this is taken away, the ouse will increase, and muscles and cockles will breed on the bed and destroy the Oysters, from gradually occupying all the places on which the spawn should be cast. There is likewise some penalty for not treading on, and killing, or throwing on shore any Star-fish (Asterias of Linnæus) that happen to be seen. These, when collected in any numbers, are very destructive to the Oyster-beds, inserting their rays, as the shells lie open, and devouring the animals within.

Oysters are not reckoned proper for the table till they are about a year and half old; so that the brood of one spring are not to be taken for sale till at least the September twelve-months afterward. When younger than these happen to be caught in the dredge, they are always thrown into the sea again. The fishermen know the age of Oysters by the broader distances or interstices among the rounds or rings of the convex shell.

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The Oysters in the pits of course always lie loose, but on their native beds they are in general fixed (from the time they are cast) by their under shell; and their goodness is said to be materially affected by their being laid in the pits with the flat shell downward, not being able in this position to retain sufficient water in the shell for their support⁕2.

The French assert, but apparently without proof, that the English Oysters, which are esteemed the best in Europe, were originally procured from Concalle Bay near St. Malo.

With regard to the locomotive faculty of the Oyster, when detached from its native rocks or habitation (which is a subject of curious investigation) every one must have observed that this cannot take place in the usual way of other bivalves, by means of a foot, for such an appendage is in it altogether wanting. The abbé Dicquemaire, who attended minutely the manners of these as well as of several other marine animals, assures us that they have a power of moving themselves, and this by the singular effort of ejecting water with considerable force from their shells. They thus are able either to throw themselves backward or to start aside in a lateral direction. He says that any person may amuse himself with the squirting and motions of Oysters, by putting them in a plate placed in a horizontal III.571 position, which contains as much sea-water as is sufficient to cover them.

The Oyster has been represented by many authors as an animal destitute not only of motion but of every species of sensation. The abbé Dicquemaire, however, has shown that it can perform movements perfectly consonant to its wants, to the dangers it apprehends, and to the enemies by which it is attacked. Instead of being destitute of sensation, Oysters are even capable of deriving some knowledge from experience. When removed from situations that are constantly covered with the sea, from want of experience, they open their shells, lose their water, and die in a few days. But, when taken from similar situations, and laid down in places from which the sea occasionally retires, they feel the effect of the sun’s rays, or of the cold air, or perhaps apprehend the attacks of enemies, and accordingly learn to keep their shells close till the tide returns⁕3.

Oysters breathe by means of gills. They draw the water in at their mouth, a small opening in the upper part of the body, drive it down a long canal that constitutes the base of the gills, and so out again, retaining the air for the necessary functions of the body. Thus their ejecting of water seems to serve the double purpose of aiding the motion of such as are loose, and of supplying the animals with air.

THE SCALLOP⁕.

The Scallop has the power of progressive motion III.572 upon land, and likewise of swimming on the surface of the water. When this animal happens to be deserted by the tide, it opens its shell to the full extent, then shuts it with a sudden jerk, by which it often rises five or six inches from the ground. In this manner it tumbles forward till it regains the water. When the sea is calm, troops or little fleets of Scallops are often observed swimming on the surface. They raise one valve of their shell above the surface, which becomes a kind of sail, while the other remains on the water, and answers the purpose of a keel, by steadying the animal, and thus preventing its being overset. When an enemy approaches, they instantly shut their shells, plunge to the bottom, and the whole fleet disappears. By what means they are enabled to regain the surface we are still ignorant.

THE MUSCLES.

The Muscle tribe is distinguished by the shell being bivalve, without any tooth in the hinge, but in having the hinge marked with a longitudinal hollow line; and by the animal’s being generally fixed to some substance by a byssus or silky beard.

Some of the Muscles penetrate into the interior of calcareous rocks, where they reside out of the reach of danger. Others adhere by their beard to the exterior of rocks or stones; and so very tenacious is their hold that, in the larger species, they cannot be III.573 separated without considerable exertion. One species is gathered, from the depths of the sea, by divers trained for the purpose, on account of the pearls that are found within the shells. Of these the ancient Romans were extravagantly fond. “It is not enough (says Pliny) to despoil the sea of its riches, in order to gorge our appetites; we must likewise, both men and women, carry them about on our hands, in our ears, upon our heads, and on our whole body.”

THE EDIBLE MUSCLE⁕.

This species is found adhering to rocks both in the European and Indian seas; but it grows to a much greater size between the Tropics than northward. It abounds on the British shores, being one of the commonest of all our shells.

All the muscles have, for an instrument of motion, a tongue or foot capable of considerable elongation, and also of being shortened into the form of a heart. This is marked with a longitudinal furrow, and completely enveloped in a sheath formed of transverse and circular fibres of an obscure purple colour. When the animal feels inclined to change its place, it thrusts the foot out of the shell, and raises itself on its edge; then, by reaching this to as great a distance as it will extend, it uses it as a kind of arm, drawing the body up to it, and thus it proceeds till it has found a convenient situation. If the III.574 Muscle be inclined to make this its residence, the instrument of its motion is now put to a very different employment, in spinning those silky threads that fix it firmly to the spot; and, like a ship at anchor, enable it to brave all the agitations of the water. This it accomplishes by seizing with its point the gluten supplied by a gland situated under its base, and drawing it out, through the furrow, into threads. When the muscle is thus fixed it lives upon the little earthy particles, or upon the bodies of such smaller animals as the water transports to its shells.

The present Muscle is generally esteemed a rich and wholesome food; but to some constitutions it often occasions disorders, the symptoms of which are great swellings, eruptions of blotches or pimples, shortness of breath, convulsive motions, and sometimes even delirium. A remedy that has been recommended is two spoons-full of oil, and one of lemon juice (or, in want of this, about two of vinegar) shaken well together, and swallowed as soon as any of the symptoms take place. This unwholesome quality has been attributed to a small species of crab, the Cancer pisum of Linnæus, that sometimes is found in the shells of the muscle. It seems, however, not to have its seat in any thing essential to the muscle; for, when accidents of this kind have happened, some persons have been affected, and others have not, who have eaten at the same time, and at least in equal quantity.

III.575

THE PEARL MUSCLE⁕.

The Pearl Muscle has a flattened and nearly orbicular shell, about eight inches long, and somewhat more in breadth. The colour of the exterior is very various, being in some individuals sea-green, in others chesnut, or even bloom colour, with white rays, and sometimes whitish, with green rays. The young shells resemble Scallops, having ears as long as the shell.

The Pearl is a calculus or morbid concretion, which is produced not only in this but sometimes even in the Common Oysters and Muscles; but in these it is generally very small, and of little value. It is found both in the body of the animal and in the shells on the outside of the body.

The principal fishery for pearls is on the coast of Tinevelly, in Eastern Hindostan, where the natives find them of such commercial importance as to employ in the fishery several hundreds of small vessels. The pearls are taken at two seasons of the year, in March and April, and again in August and September. They do not, however, fish every year; for if, upon trial, they do not find the pearls sufficiently valuable, they abstain till the ensuing season to allow them time to increase their size.

A cord is fastened under the arms of the divers, and held by the persons in the boat; and, to accelerate their descent, the divers have a perforated III.576 stone of eighteen or twenty pounds weight tied with a cord to their great toe. Each of them is also furnished with a sack, that has the mouth distended by a hoop. They then descend, and, on reaching the bottom, slip off the stone, which is drawn up, and fill their sack with shells. When this is full they give a signal by pulling the rope, and they are then drawn up by the men in the boats.

The depth of the water is twenty or thirty yards, and the distance from shore four or five leagues. When drawn up they rest eight or ten minutes, to recover their breath, and then plunge in again; and a succession of men continue this slavish employment for ten or twelve hours every day. The shells are left in vast heaps to putrefy till the season is over. The gains of the adventurers are often small, as the success is very precarious. Great pearls are but seldom found, and the generality of what are taken are of the smaller kind, called Seed Pearls, which are sold by the ounce to be converted into powder.

The shells are found adhering to the coral banks. Numbers of sharks lurk about the diving-places, which often devour the poor adventurers⁕1.

THE ARGONAUTS.

In this tribe the shell is univalve, spiral, involute, and membranaceous, with only a single cell.

III.577

THE PAPER NAUTILUS, OR ARGONAUT⁕,

which is six or eight inches in length, and but little either thicker or stronger than paper, is found in the Mediterranean Sea, and in the Indian Ocean. It is the famous Nautilus of the ancients, and is supposed, in the early ages of society, to have furnished the original idea of navigation:

When it means to sail, it discharges a quantity of water from its shell, by which it is rendered lighter than the surrounding medium, and of course rises to the surface. Here it extends two of its arms upward, which are each furnished at their extremity with an oval membrane that serves as a sail. The other six arms hang over the sides of the shell, and supply the place either of oars or rudder.

In some places, when the sea is not agitated by winds, great numbers of these singular creatures may sometimes be seen diverting themselves by sailing about in this manner; but as soon as a storm rises, or any thing gives them disturbance, they retract their arms, take in as much water as renders them somewhat heavier than that in which they swim, and then sink to the bottom. Several of them were observed by M. Le Vaillant on the sea near the Cape of Good Hope; and, as he was desirous of obtaining perfect specimens of the shells, he sent some of his people into the water to catch them: but, when the men had got their hands within a certain distance, they always instantly sank, and, with all the art that could be employed, they were not able to lay hold of a single one. The instinct of the animal showed itself superior to all their subtilty; and, when their disappointed master called them away from their attempts, they expressed themselves not a little chagrined at being outwitted by a shell-fish⁕1.

This species, which is the real Nautilus of the ancients, is not to be confounded with the Chambered or Pearly Nautilus, which belongs to a different tribe, and bears very little resemblance to the present, either in its construction or habits.—The III.579 animal, if seen detached from its shell, might be mistaken for a Sepia, bearing so great a resemblance to the Sepia Octopus, or light-armed Cuttle-fish, that its principal difference consists only in the shape of those arms that are used as sails.

SNAILS.

The Snails have a spiral and somewhat pellucid shell, the aperture of which is roundish. Their bodies, in general construction, are similar to those of the Slugs.

The wise Author of Nature has denied to these animals the use of feet and claws to enable them to move from place to place, but he has made them ample amends in a way more commodious to their habits and mode of life, by the broad skin along each side of the belly, and the power of motion that this possesses. By this motion they are enabled to creep, and by the skin, assisted with the glutinous slime emitted from their body, they adhere firmly and securely even to the smoothest surfaces.

When the Snail is in motion, four horns are distinctly seen proceeding from its head; but the two uppermost and longest of these deserve peculiar consideration, both on account of the various motions with which they are endued, and also from their having eyes fixed at the extreme ends of them. These appear like two blackish points, and when taken from the body are of a bulbous figure. III.580 They have but one coat; and the vitreous, the aqueous, and the crystalline humours are (though not very distinctly) to be seen. These eyes the animal can direct to different objects at pleasure, by a regular motion out of the body; and sometimes it hides them, by a very swift contraction into the belly. Under the smaller horns is the animal’s mouth; and though its substance may appear too soft to be furnished with teeth, yet it has no fewer than eight.—With these it chews leaves and other substances, seemingly harder than any part of its own body; and with these it even sometimes bites off pieces of its own shell.

The snail, when its shell is broken, has a power of mending it. Sometimes the animals are seemingly crushed to pieces; and, to all appearance, utterly destroyed; yet still they set themselves to work, and with the slimy substance that they force from their bodies, which soon hardens, they in a few days mend all their numerous breaches. All the junctures, however, are very easily seen; for these have a fresher colour than the rest, and the whole shell in some measure resembles an old coat patched with new pieces. They are sometimes seen with eight or ten of these patches. Still, however, though the animal has the power of mending its shell, it cannot, when come to its full growth, make a new one.—Swammerdam tried the experiment. He stripped a snail of its shell, without injuring any of the blood-vessels, retaining that part of the shell where the muscles were inserted: but it died in three days after it lost its covering; not, however, without making III.581 efforts to build up a new shell; for, before its death, it pressed out a certain membrane round the whole surface of its body. This membrane was entirely of the shelly nature, and was intended, no doubt, as a supply toward a new one.

The following instances of tenacity of life in snails are well authenticated, and probably without parallel in any other division of the animal creation.

Mr. Stuckey Simon, a merchant of Dublin, whose father, a fellow of the Royal Society and a lover of natural history, left to him a small collection of fossils and other curiosities, had among them the shells of some snails. About fifteen years after his father’s death (in whose possession they continued many years) he by chance gave to his son, a child about ten years old, some of these snail-shells to play with. The boy put them into a flower-pot, which he filled with water, and the next day into a bason. Having occasion to use this, Mr. S. observed that the animals had come out of their shells. He examined the child, who assured him that they were the same he had given him, and said he had also a few more, which he brought. Mr. S. put one of these into water, and in an hour and a half after observed that it had put out its horns and body, which it moved but slowly, probably from weakness. Major Vallancy and Dr. Span were afterward present, and saw one of the snails crawl out, the others being dead, most probably from their having remained some days in the water. Dr. Quin and Dr. Rutty also examined the living snail several different times, and were greatly pleased to see him come out of his III.582 solitary habitation after so many years confinement. Dr. Macbride, and a party of gentlemen at his house, were also witnesses of this surprising phenomenon. Dr. Macbride has thus mentioned the circumstance: “After the shell had lain about ten minutes in a glass of water that had the cold barely taken off, the snail began to appear; and in five minutes more we perceived half the body pushed out from the cavity of the shell. We then removed it into a basin, that the snail might have more scope than it had in the glass; and here, in a very short time, we saw it get above the surface of the water, and crawl up toward the edge of the basin. While it was thus moving about, with its horns erect, a fly chanced to be hovering near, and, perceiving the snail, darted down upon it. The little animal instantly withdrew itself into the shell, but as quickly came forth again when it found the enemy was gone off. We allowed it to wander about the basin for upward of an hour, when we returned it into a wide-mouthed phial, wherein Mr. Simon had lately been used to keep it. He was so obliging as to present me with this remarkable shell; and I observed, at twelve o’clock, as I was going to bed, that the snail was still in motion; but next morning I found it in a torpid state, sticking to the side of the glass.”

A few weeks afterward this shell was sent to Sir John Pringle, who shewed it at a meeting of the Royal Society; but some of the members imagining that Mr. Simon must have been imposed upon by his son having substituted fresh shells for those that had been given to him, the boy was re-examined III.583 by Dr. Macbride on the subject, who declared that he could find no reason to believe that the child either did or could impose upon his father. Mr. Simon’s living in the heart of the city rendered it almost impossible for the boy (if he had been so disposed) to collect fresh shells, being at that time confined to the house with a cold. Mr. Simon has also declared that he is positive those were the shells he gave to him, having in his cabinet many more of the same sort, and nearly of the same size⁕1.

In consequence of the account, from which the above was extracted, appearing in some periodical publication, the following letter, bearing every mark of authenticity, was sent by a Mr. Rowe to the editors of the Annual Register; he states it to have been written by a lady, but her name he was not at liberty to mention.

“There is, in the last magazine, an account of the reviving of some snails which had lain in Mr. Simon’s cabinet fifteen years. Is it not a most extraordinary story? And yet I am not faithless in that point, as many a reader probably is; for I once saw a very remarkable property in snails which gave me such uneasiness as fixed the remembrance strongly in my mind to this minute, though it happened many years ago.

“I was at Wrotham, at Mr. Haddock’s in Kent, and was making a little shell-work tower, to stand on a cabinet in a long gallery. After having repaired III.584 two small amber temples to grace the corners, I was desirous of having some odd pretty ornament in front; and sea-shells running short before I had finished, I recollected having seen some pretty little snails on the chalk hills there; and we all went one evening to pick up some, and found variety of forms, and colours, and sizes. We returned home weary enough, and longed for tea, though it was somewhat late, and a large boiler was brought in, as we were a round company. I was contriving how to kill the snails in the easiest and most merciful manner, when a wag said, ‘Stick them on alive;’ at which I shuddered, and called him brute. At length I got a large china basin and, putting a handful or two of snails into it, I filled it up with boiling water; and though my heart recoiled at the deed, yet my eagerness to finish my work next morning conquered my compassion. To make sure of giving my snails the coup-de-grace, I poured off the first water, and then filled the bowl again with more out of the hot-boiling kettle. I carried the basin into a summer-house in the garden, where I loved to go to work early in a morning, before my friends were stirring, and the next morning I arose sooner than common, and went into the summer-house: but how great was my surprise to find my poor snails crawling about, some on the edge of the basin, some tumbling over, some on the table, and one or two actually eating the paste that was to stick them on! I was perfectly shocked, and burst into tears, and, picking up every snail carefully, carried them into a field beyond the garden, where I make no doubt, III.585 but they perfectly recovered their scaldings in boiling water.

“I had an abundance of empty shells of the same kind, but they had not the beauty of those which had snails in them. However, I used those only which I could apply without cruelty and compunction. This I then thought a very surprising event, but Mr. Simon’s snails, I must confess, are far superior to mine⁕2.”

From various experiments that have been made on Snails, it appears that they are possessed of considerable powers of reproduction. Spallanzani found that the whole head might be cut off, and that in a certain time another would be formed.

THE GARDEN SNAIL⁕.

The mode of breeding, in this and a few other species of snails, is extremely curious, and too well authenticated to be doubted. At a certain time of the year they meet in pairs, and, stationing themselves an inch or two apart, launch several little darts, not quite half an inch long, at each other.—These are of a horny substance, and sharply pointed at one end. The animals, during the breeding season, are provided with a little reservoir for them, situated within the neck, and opening on the right III.586 side. On the discharge of the first dart the wounded Snail immediately retaliates on its aggressor by ejecting at it a similar one: the other renews the battle, and in turn is again wounded. Thus are the darts of Cupid, metaphorical with all the rest of the creation, here completely realized in Snails. After the combat they come together. Each of them lays its eggs in some sheltered and moist situation, generally under a little clod of earth, or in some cool cavity. The eggs are about the size of small peas, semi-transparent, and of a soft substance. From these the young are hatched completely formed, with shells on their backs; and they undergo no further change than what necessarily takes place in the gradual increase of their size.

The depredations that these animals commit in gardens and orchards are very considerable; and it is remarkable that in defect of moist and succulent food, as fruit and tender leaves, they will even attack substances of a dry and hard nature. The common Garden Snail has been known, when confined for a single night under glass of more than four inches in diameter placed on a sheet of common blue paper, entirely to devour the whole paper contained in the included space, to the very edge of the glass, so that a circular piece seemed almost as neatly taken out as if it had been marked by a pair of compasses⁕1.

III.587

THE ESCULENT SNAIL⁕.

This is the largest of all the Land Snails produced in this country. It is found in the woods and under hedges in Northamptonshire and some others of the southern counties.

At the commencement of winter it carefully closes up its shell with a thick white cover, or operculum, attached to its body, that just fills up the opening, and in this inclosed state remains till the commencement of warm weather, seldom appearing abroad till about the beginning of April.

It is large and fleshy, and, when properly cooked, not unpleasant to the taste. Among the Romans it constituted a favourite dish; but, if the account of Varro is to be credited, they had it of a size infinitely larger than any now known, for this writer assures us that the shells of some of them would hold ten quarts. They kept these animals in what were called the Cochlearia or Snail Stews. These were generally made under rocks or eminences, whose bottoms were watered by lakes or rivers; and if a natural dew or moisture was not found, they formed an artificial one by bringing a pipe into the place bored full of holes like a watering-pot, through which it was continually sprinkled. They required little attendance or food, supplying themselves, in a great measure, as they crawled about the sides or floor of their habitation. To fatten III.588 them, however, they were fed with bran and sodden lees of wine⁕1.

They are even yet much admired in some parts of the Continent, and not always used from economical motives; for at Vienna, but a few years ago, seven of them were charged the same at an inn as a plate of veal or beef. The usual modes of preparing them for the table are either boiling, frying them in butter, or sometimes stuffing them with farce meat: but, in what manner soever they are dressed, their sliminess always in a great measure remains. The greatest quantities and the finest Snails are brought from Suabia. Dr. Browne, who travelled to Vienna above a century ago, remarks that, since the markets were so well supplied with other provisions, “he was surprised to meet with some odd dishes at their tables, as Guinea-pigs, and divers sorts of Snails and Tortoises.”

Dr. Townson was shewn at Erlau a snailery, which the proprietor informed him was constructed on an improved plan. In our island, he says, this might have had the denomination of a Patent Snailery, or Philosophical Snail-sty. It consisted only of a large hole, two or three feet deep, dug in the around, having a wooden house as a cover. The animals in this place were fed on the refuse of the garden, which was thrown into them⁕2.

There seems some doubt as to the original introduction of these snails into England: Pennant says III.589 it was by sir Kenelm Digby; and Da Costa that a Charles Howard, esq., of the Arundel family, brought some of them, in the last century, from Italy, in the hopes of rendering them an article of food in this country, and for this purpose dispersed them about the woods and downs of Albury, an ancient seat of that family near Boxhill in Surry. They are now to be found in considerable plenty, not only there, but in parts of the confines of Sussex.

III.590

ZOOPHYTES⁕1.

The creatures that are ranked under this order seem to hold a middle station between animals and vegetables. Most of them, deprived altogether of loco-motion, are fixed by stems that take root in crevices of rocks, among sand, or in such other situations as nature has destined for their abode: these by degrees send off branches, till at length some of them attain the size and extent of large shrubs. The Zoophytes are usually considered under two divisions. The stony branches of the first division, which has the general appellation of Coral, are hollow, and full of cells, the habitations of animals resembling Polypes, Medusæ, &c. according to their respective genera. They consist of the Tubipores, Madrepores, Millepores, and Cellepores; and are nearly all confined to the ocean. The animals appear at the ends of the branches, where they have somewhat the resemblance of animated blossoms endowed with considerable spontaneous motion. The stems of some of the Millepores are almost solid, the cells being so extremely small as to be scarcely visible without high magnifying powers. Among these is the Millepora Polymorpha, or Officinal Coral of the shops.

III.591

The next division of the present order consists of such animals as have softer stems, and are in genera! not merely inhabitants of a stem or branches, but are themselves in the form of a plant. Those best known are the Corallines, the Sponges, and the Polypes.

The Corallines are composed of capillary tubes whose extremities pass through a calcareous crust, and open into pores on the surface. They are entirely submarine, and from their branches being finely divided and jointed, resembling some species of Lichen, they have, till late years, been arranged by botanists with the cryptogamous plants. In appearance they certainly approach very nearly to some of the vegetables; but their calcareous covering alone is sufficient demonstration of their being allied, in however humble a station, to a more elevated order of beings.

The Sponges consist of an entirely ramified mass of capillary tubes, supposed by many to be the production of a species of worms which are often found straying about their cavities. This idea is now, however, nearly exploded. Others have imagined them mere vegetables. But that they are possessed of a living principle seems evident from the circumstance of their alternately contracting and dilating their pores, and shrinking in some degree from the touch whenever examined in their native waters. From their structure they are capable of absorbing nutriment from the fluid in which they are by nature immersed. They are the most torpid of all the Zoophytes. The species differ very III.592 greatly from each other both in shape and structure. Some are composed of reticulated fibres or masses of small spines: some, as the Common or Officinal Sponge, are of no regular shape; others are cup-shaped, others tubular, &c.

The Officinal Sponge is elastic, and very full of holes: it grows into irregular lobes of a woolly consistence, and generally adheres, by a very broad base, to the rocks. It is chiefly found about the islands in the Mediterranean sea, where it forms a considerable article of commerce. A variety of small marine animals pierce and gnaw into its irregular winding cavities. These appear on the outside, by large holes raised higher than the rest. When it is cut perpendicularly, the interior parts are seen to consist of small tubes, which divide into branches as they appear on the surface. These tubes, which are composed of reticulated fibres, extend themselves every way, by this means increasing the surface of the sponge, and ending at the outside in an infinite number of small circular holes, which are the proper mouths of the animal. Each of these holes is surrounded by a few erect pointed fibres, that appear as if woven in the form of little spines. These tubes, with their ramifications, in the living state of the sponge, are clothed with a gelatinous substance, properly called the flesh of the animal. When the sponge is first taken it has a strong fishy smell, and the fishermen take great care to wash it perfectly clean, in order to prevent its growing putrid.

III.593

The Polypes⁕2 are gelatinous animals, consisting of a long tubular body, fixed at the base, and surrounded at the mouth by arms or tentacula. They are chiefly inhabitants of fresh waters, and are among the most wonderful productions of nature. The particulars of their life, their mode of propagation, and powers of reproduction, after being cut to pieces, are truly astonishing to a reflecting mind. Long after experi­ments had been made did scepticism involve the philosophic world; and the history of the animals did not obtain complete credit till these had not only been often repeated but varied in every possible manner: they at length, however, incontestably proved the truth of the surprising and apparently impossible properties.

The Green Polype, a species that will fully illustrate the nature of the whole tribe, is found in clear waters, and may generally be seen in great plenty in small ditches and trenches of fields, especially in the months of April and May. It affixes itself to the under parts of leaves, and to the stalks of such vegetables as happen to grow immersed in the same water. The animal consists of a long tubular body, the head of which is furnished with eight and sometimes ten long arms or tentacula that surround the mouth. It is capable of contracting its III.594 body in a very sudden manner when disturbed, so as to appear only like a roundish green spot; and, when the danger is over, it again extends itself as before.

It is of an extremely predacious nature, and feeds on the various species of small worms, and other water animals that happen to approach. When any animal of this kind passes near the Polype, it suddenly catches it with its arms, and, dragging it to its mouth, swallows it by degrees, much in the same manner as a snake swallows a frog. Two of them may sometimes be seen in the act of seizing the same worm at different ends, and dragging it in opposite directions with great force. It often happens that, while one is swallowing its respective end, the other is also employed in the same manner; and thus they continue swallowing each his part, until their mouths meet together: they then rest each for some time in this situation, till the worm breaks between them, and each goes off with his share. But it often happens that a seemingly more dangerous combat ensues, when the mouth of both are thus joined together upon one common prey: the largest Polype then gapes and swallows his antagonist; but, what is most wonderful, the animal thus swallowed seems to be rather a gainer by the misfortune. After it has lain in the conqueror’s body for about an hour it issues unhurt, and often in possession of the prey that had been the original cause of contention. The remains of the animals on which the Polype feeds, are evacuated at the mouth, the only opening in the body. It is capable III.595 of swallowing a worm of thrice its own size: this circumstance, though it may appear incredible, is easily understood when we consider that the body of the Polype is extremely extensile, and is dilated on such occasions to a surprising degree.

The species are multiplied for the most part by vegetation, one or two, or even more young ones emerging gradually from the sides of the parent animal; and these young are frequently again prolific before they drop off: so that it is no uncommon thing to see two or three generations at once on the same Polype.

But the most astonishing particular respecting this animal is that if the Polype be cut in pieces it is not destroyed, but is multiplied by dissection: it is literally

It may be cut in every direction that fancy may suggest, and even into very minute divisions, and not only the parent stock will remain uninjured but every section will become a perfect animal. Even when turned inside-out it suffers no material injury; for, in this state, it will soon begin to take food, and to perform all its other natural functions.

Leuwenhoek was the first who discovered this animal, toward the end of the seventeenth century; but M. Trembley, of Geneva, made, in the year 1740, the first experi­ments that proved decisively its properties. In the course of his experi­ments, he found that different portions of one Polype could be engrafted on another. Two transverse sections III.596 brought into contact will quickly unite, and form one animal, though each section belong to a different species. The head of one species may be engrafted on the body of another. When one Polype is introduced by the tail into another’s body, the two heads unite, and form one individual. Pursuing these strange operations, M. Trembley gave scope to his fancy, and, by repeatedly splitting the head and part of the body, formed hydras more complicated than ever struck the imagination of the most romantic fabulists.

These creatures continue active during the greatest part of the year, and it is only when the cold is most intense that they feel the general torpor of nature. All their faculties are then for two or three months suspended; but if they abstain at one time they have ample amends in their voracity at another; and, like all those animals that become torpid in winter, the meal of one day suffices for several months.

III.597

ANIMALCULES⁕1.

These animals are very simple in their form, and generally invisible without a magnifying power.—They are chiefly found in infusions of animal and vegetable substances.

Their multiplication long occupied the attention and eluded the researches of philosophers. The discovery, however, a few years back, that some of the larger animals increased by a spontaneous division, gave rise to the conjecture that these microscopic animalcules might multiply their numbers in a similar manner. This conjecture was communicated to M. de Saussure in a letter from Bonnet, who received an answer from Genoa in September 1769, to the following purport:

“What you propose as a doubt (says M. de Saussure) I have verified by incontestable experi­ments, namely, that infusion animalcules multiply by continued divisions and subdivisions. Those roundish or oval animalcules that have no beak or hook on the fore-part of their bodies, divide transversely. A kind of stricture or strangulation begins about the middle of the body, which gradually increases, till the two parts adhere by a small thread only. Then both parts make repeated efforts, till III.598 the division is completed. For some time subsequent to the separation the two animals remain in a seemingly torpid state; but they afterward begin to swim about briskly. Each part is only one half the size of the whole: but they soon acquire the magnitude peculiar to the species, and multiply by similar divisions. To obviate every doubt, I put a single animalcule into a drop of water, which split before my eyes. Next day I had five, the day after sixty, and on the third day their number was so great that it was impossible to count them.

“Another species, with a beak or horn on the fore-part of its body, which I obtained from an infusion of hemp-seed, multiplied likewise by division, but in a manner still more singular than the former. This animalcule, when about to divide, attaches itself to the bottom of the infusion, contracts its body, which is naturally oblong, into a spherical form, so that the beak entirely disappears. It then begins to move briskly round, sometimes from right to left, and sometimes from left to right, the centre of motion being always fixed. Towards the end, its motion accelerates, and, instead of an uniform sphere, two cross-like divisions begin to appear. Soon after, the creature is greatly agitated, and splits into four animalcules, perfectly similar to, though smaller than, that from which they were produced. These four increase to the usual size, and each in its turn subdivides into other four⁕2.”

III.599

The different kinds of animalcules are very numerous; on which account I shall confine my observations to a few of the most curious genera, namely Vorticella, Vibrio, and Volvox.

Of these the Vorticella, or wheel animals, are the most remarkable both in their structure, their habits, and production. In general form they bear a great affinity to the Polypes, having a contractile naked body, furnished with rotatory organs round the mouth; and indeed many microscopical writers have denominated them Cluster-polypes. They are very small, and generally found in clear stagnant waters, during the summer months, attached to the stalks of the lesser water plants, where they feed on animalcules still smaller than themselves. Many of the species are found in groupes, sometimes formed by the mere approximation of several individuals, and at other times by the ramified or aggregate manner in which they grow. Their various motions, like those of the Polypes, are generally exerted only for the purpose of obtaining prey, the rotatory motion of their tentacula causing an eddy in the water around each individual sufficient to attract into its vortex such animalcules as happen to swim near: these the little creature seizes by suddenly contracting its tentacula and inclosing them in the midst. The stems of several of the species, into which they occasionally withdraw themselves, are somewhat rigid or scaly. The young are carried in oval integuments on the outside of the lower part of these; and, when ready to come forth, the parents aid their extrusion, where such is necessary, by III.600 writhing their bodies, or striking the little vesicle. As soon as the young one is liberated from its prison it fixes itself, and commences the necessary operations to procure its food.

The animals of the genus Vibrio are very simple, round, and elongated worms, nearly all invisible to the naked eye. The species best known is the Eel Vibrio⁕3, which is found in sour paste, and in most sediments from an infusion of grain. Its body is pellucid, and tapers toward both ends. The general resemblance that it bears to an Eel has almost universally led microscopical writers to distinguish it by that title, though its most gigantic individuals are seldom a tenth of an inch in length. When paste becomes sour, if examined with a glass it will be seen to contain multitudes of these animalcules, moving about with great strength and rapidity in every direction. And animals very similar in appearance are also frequently to be observed in vinegar. They are viviparous, and produce, at intervals, a numerous progeny. If one of them be cut through the middle, several young ones, coiled up and inclosed each in a membrane, will be seen to issue from the wound. Upwards of a hundred young have been remarked to proceed from a single parent; which readily accounts for their sudden and prodigious increase.—The Proteus Vibrio is a species that has its name from its very singular power of assuming different shapes, so as sometimes III.601 with difficulty to be distinguished for the same animal. When water, in which any vegetable has been infused, or in which any animal substance is preserved, has stood undisturbed for some days, a slimy substance will be found on the sides of the vessel, some of which, if viewed in a microscope, will be found to contain, among several other animalcules, the Proteus. It is pellucid and gelatinous, and swims about, most commonly, with a long neck and bulbous body, with great vivacity. Sometimes it makes a stop for a minute or two, and stretches itself out apparently in search of prey.—When alarmed it immediately draws in its neck, becomes more opake, and moves very sluggishly. It will then, perhaps, instead of its former long neck, push out a kind of wheel machinery, the motions of which draw a current of water, and, along with this, probably its prey. Withdrawing this it will sometimes remain almost motionless for some seconds, as if weary; then protruding its long neck will often resume its former agility, or instead adopt in succession a multitude of different appearances. The eyes of this creature have not hitherto been discovered: it however swims with great rapidity among the multitudes of animalcules that inhabit the same water, without striking against them.

I shall conclude this account of the Animal Creation with La Martiniere’s description of Volvox bulla, a species of animals nearly the most simple of any that have yet come to our knowledge. “They consist (he says) only of oval bodies, similar in appearance III.602 to soap bubbles, arranged in parties of three, five, six, and nine: among them are also some solitary ones. These collections of globules, being put into a glass filled with sea-water, described a rapid circle round the glass by a common movement, to which each individual contributed by the simple compression of the sides of its body, probably the effect of the reaction of the air with which they were filled. It is not, however, easy to conceive how these distinct animals (for they may be readily separated without deranging their economy) are capable of concurring in a common motion. These considerations, together with the form of the animal, recalled to my mind, with much satisfaction, the ingenious system of M. de Buffon; and I endeavoured to persuade myself that I was about to witness one of the most wonderful phenomena of nature, supposing that these molecules, which were now employed in increasing or diminishing their number, or performing their revolutions in the glass, would soon assume the form of a new animal, of which they were the living materials. My impatience led me to detach two from the most numerous group, imagining that this number might perhaps be more favourable to the expected metamorphosis. I was, however, mistaken. These I examined with more attention than the rest, and the following account is of their proceedings alone. Like two strong and active wrestlers, they immediately rushed together, and attacked each other on every side: sometimes one would dive, leaving its adversary at the surface of the water; one would III.603 describe a circular movement, while the other remained at rest in the centre: their motions at length became so rapid as no longer to allow me to distinguish the one from the other. Having quitted them for a short time, on my return I found them reunited as before, and amicably moving round the edge of the glass by their common exertions.”

FINIS.

INDEX
to the
ENGLISH NAMES and SYNONYMS.

Those marked with an * are varieties of some other species; and those printed in Italics are Synonyms.

	Page.
Actinia Tribe	542
—— Sea Anemone	543
—— Purple Anemone	544
—— Sea Marigold	547
Anemone, Sea	542
—— purple	544
Animalcules	597
Argonaut Tribe	576
—— Paper Nautilus	577
Basket fish	553
Bernacle Tribe	559
—— common	559
—— goose	559
606 Cuttle-fish Tribe	549
Dew-worm	532
Earth-worm Tribe	532
—— Dew-worm	532
Echinus common	555
—— eatable	555
607 Furia	528
Guinea worm	526
Hair-worm Tribe	530
—— common	530
—— water	530
Leech Tribe	535
—— medicinal	535
Limax spinning	538
Marigold sea	547
608 Muscle Tribe	572
—— edible	573
—— pearl	575
Nautilus, paper	577
Nereis Tribe	540
—— night-shining	540
—— Scallop	571
Pholas Tribe	560
—— dactyle	561
Polype	593
—— green	593
Razor-shell Tribe	565
Sea stars	552
Sea-urchin Tribe	555
—— common	555
—— Common Echinus	555
—— Eatable Echinus	555
Slug Tribe	537
—— spinning	538
Snail Tribe	579
—— garden	585
—— esculent	587
Spunge	591
—— officinal	592
Star-fish Tribe	552
—— arborescent	553
609 —— Magellanic	553
—— Basket-fish	553
—— branched asterias	553
—— Medusa	553
Tape-worm Tribe	520
—— common	523
Tæniæ	520
Thread-worm Tribe	525
—— Indian or Guinea-worm	526
Vibrio	600
—— eel	600
—— proteus	600
Volvox bulla	601
Vorticella	599
Worms	519
Zoophytes	590

LINNÆAN;
or,
SYSTEMATIC INDEX.

	Page.
VERMES	519
Intestina.
Tænia Genus	520
—— solium	523
Filaria Genus	525
—— medinensis	526
Furia Genus	528
—— infernalis	528
Gordius Genus	530
—— aquaticus	530
Lumbricus Genus	532
—— terrestris	532
Hirudo Genus	535
—— medicinalis	535
Mollusca.
Limax Genus	537
—— agrestis	538
Nereis Genus	540
—— noctiluca	540
Actinia Genus	542
—— anemonoides	543
—— rufa	544
—— calendula	547
Sepia Genus	549
Asterias Genus	552
—— medusæ	553
Echinus Genus	555
—— esculentus	555
Testacea.
Lepas Genus	559
Pholas Genus	560
—— dactylus	561
Solen Genus	565
Ostrea Genus	567
—— edulis	567
—— maxima	571
Mytilus Genus	572
—— edulis	573
—— margaritiferens	575
Argonauta Genus	576
—— argo	577
Helix Genus	579
—— hortensis	585
—— pomatia	587
Zoophyta	590
Animalcula	597