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in beauty. They inhabit tubes of a horny or tendinous substance, the greater part of which is buried in the sand, or mud, at the bottom of the sea. From the upper extremity of these tubes, they push out a great number of elegant tentacula, which are arranged about the mouth like rays from the centre of a circle.

The species are numerous; and several beautiful kinds have, of late years, been discovered to inhabit the English coasts.

THE FUNNEL-SHAPED

*

AND VOLUTACORN AMPHITRITE †.

Each of these singular and extremely beautiful animals, is of late acquisition to the Natural History of the British Islands; and, for the discovery of them, in the neighbourhood of Kingsbridge, Devon, we are in

when expanded, are arranged like radii from the centre of a circle, and in two divisions. On each side of the body, through its whole length, there is a row of minute peduncles or feet.

* DESCRIPTION. The body is long, and consists of from a hundred and fifty to a hundred and sixty joints. These are distant, and of an orange-colour, with whitish rings. At the base of the tentacula or feelers there is a scalloped membrane. The tentacula are two in number, semicircular when spread, and nearly uniting into a regular circle: they are each composed of about thirty-seven rays, connected by a transparent web, except at the points. Their outside is smooth, and of a purple colour. The inside is elegantly ciliated with two rows of fimbriæ along each ray, of a chesnut-colour, shaded to a purple near the centre. The mouth is purple, and the lips are bordered with chesnut.

SYNONYM. Amphitrite infundibulum. Montagu, in Linn.

Tran.

+ DESCRIPTION. The length of this species is about five inches, and the tentacula are somewhat more than an inch long. The stem is furnished with long ciliated fibres on one side. The plumes of the tentacula are of a light yellowish brown, banded and mottled with chesnut.

SYNONYM. Amphitrite volutacornis. Montagu, in Linn.

Tran.

debted to the indefatigable researches of Col. Montagu.

The former inhabits a case or tube of a gelatinous but firm and elastic nature. These cases are buried beneath the surface of the sand; and, when uncovered, as they sometimes are, by the lowest ebb of the springtides, their situation is only discoverable by a small portion of them above, appearing not unlike a black jelly. When the tide returns, the animals display their beautiful tentacula, but they rarely expose their body. If dug up, and confined in a glass of sea-water, they sicken in the course of a few days; and, if the water be not changed, they soon evacuate their tubes and die.

In their native abode, observes Col. Montagu, (in the Linnean Transactions,) they recede on the least alarm; and when the gelatinous case is taken into the hand, and the animal is extended within it, the sudden contraction, within the tremulous tube, produces a singular and instantaneous vibrative shock to the parts in contact, which, from its being unexpected, creates surprise.

The Funnel-shaped Amphitrites are found in the Estuary of Kingsbridge, near the Salt-stone, but are by no means of frequent occurrence there. Their food is supposed to consist of the smaller species of marine worms. These they guide towards their mouth by a whirling motion, which they make by means of their tentacula.

The Volutacorn Amphitrite was taken in the sea near Kingsbridge, in the dredges which are employed for the catching of oysters. The specimen described by Col. Montagu was brought to him alive, in sea-water. In this situation he had an opportunity of examining carefully the curious structure of its beautiful tentacula, which, he says, far exceed, in delicacy, the finest pencil of the artist. They are not retractile, but are capable of greater or less extension.

The interior conformation of these animals appears

to consist chiefly of a stomach and three tubes, similar to intestines, of which one appears to perform the functions of the heart, or at least to form the principal centre of their vascular system.

OF THE NEREIS TRIBE*.

These are all marine animals. They are very various in size; some are invisibly minute, and others are several inches in length. They have been denominated Marine Scolopendræ or Centipedes; and, in some respects, they bear a strong resemblance to these animals.

By numerous legs with which they are furnished, they are enabled to move about among submarine rocks and stones, with considerable agility. Under these they conceal themselves, and lie in ambush for their prey, which chiefly consists of minute worms of different kinds.

THE PELAGIC NEREIS †, AND NIGHT-SHINING NEREIS. The animals of this species reside at the bottom of

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.

+ DESCRIPTION. This species is usually about seven inches in length. The back is convex, and has a scarlet line down the middle. Between the eyes there is a triangular white spot, and there are two others at the sides. The body is of a tawny colour; and the peduncles, or feet, are cirrate and warty.

SYNONYMS. Nereis pelagica. Linn.-Néreïde pélasgienne.

Bosc.

DESCRIPTION. The Night-shining Nereis is oblong, linear, and so minute as to escape examination by the naked eye. The body, composed of about twenty-three segments or

the sea, among the roots of sea-weeds, concealed beneath stones, and in empty shells. Here they sometimes spin a kind of silken net. They also bury themselves in the sand, occasionally lining their holes with a similar substance. In the places of their concealment they lie in wait for prey, darting the anterior part of their body suddenly out, as any small animal passes them, and seizing it in their powerful jaws.

If one of these animals be cut into two or three parts, the fragments will continue to move for a considerable time afterwards. But all these die except that part to which the head is attached: this recovers from the injury it has sustained, and becomes a perfect animal.

The Pelagic Nereis is not very uncommon on the British coasts.

The Night-shining Nereis.-These minute creatures inhabit every sea; and are one of the causes of the luminous shining of the water in the night. They are found on all kinds of marine plants; but often leave them, and swim on the surface of the water. They are frequent at every season of the year, but particularly in summer, before stormy weather, when they become more agitated and more luminous than at other times. So minute are they, that myriads of them may be contained in a small cup full 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, be indebted for their luminous quality. have observed with great attention (says Barbut) a fish just caught out of the sea, the body of which was almost covered with them; and I have examined them in the dark. They twist and curl themselves with

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joints, is scarcely two lines long. It is quite pellucid, and its colour a water-green. Linnæus.-La Néreïde

SYNONYMS. Nereis noctiluca. Phosphorique. Cuvier. Bosc.

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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. These animals do not shine in the day-time, because the solar rays are too powerful for their light, however aggregate, or however immense their number.

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 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 luminous properties.

OF THE ACTINIE, OR SEA-ANEMONES.

These animals are of a somewhat oblong form, and, when closed, resemble a truncated cone. They are fixed by the base; and from the upper part of their body occasionally extend several tentacula, which are disposed in regular circles. The mouth 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 by means of their arms; and they eject the shells and other indigestible parts through the same opening. It, however, sometimes happens, 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 the shell is forced through the body, making a wound, as if with a knife, near the base. The arms of the Sea-anemones seem to lay

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