Mr. Bingley describes an animal of this kind, which he kept by him for some time alive; it had more than four thousand tentacula on the under sides of the rays. These it frequently retracted, and again pushed out, as a snail does its horns; and by means of them it was enabled firmly to adhere to the dish containing the salt-water in which it was kept. Whenever he touched the tentacula with his finger, all those of that ray or limb were gradually withdrawn, but those of the other rays were not in the least affected by it.
There are many other kinds of Star-fishes, especially in warm climates. Amongst our native species we may notice the Great Sun Star (Solaster papposa) with a large disc and thirteen short rays; the Luidia fragilissima with five long rays, which it usually casts off immediately on finding itself in danger, so as to render it a most difficult matter to obtain perfect specimens of this species. The Feathered Star (Comatula rosacea) is also deserving of mention.—This is a small species, with the arms distinct from the body as in the last species and jointed, but furnished with numerous slender jointed tentacles which give them the appearance of plumes. There are ten of these arms and the number of little calcareous joints contained in them is most astonishing. The small cuplike body of the Feather Star bears other slender jointed appendages, by means of which the creature clings to the rocks with its mouth and arms directed upwards; and in the young state it is even supported on a jointed stalk, from which it eventually casts itself free.
THE SEA-URCHIN. (Echinus miliaris.)
This animal, which lodges in the cavities of rocks just beneath low-water mark, on most of the British coasts, is nearly of a globular shape, not much unlike that of an orange, having its shell marked into ten partitions, with rows of projections like beads, which divide it. On the outside of the shell there are a great number of sharp, moveable spines, of a dull violet and greenish colour, curiously articulated, like balls and sockets, with tubercles on the surface, and connected by strong ligaments to the skin or epidermis with which the shell is covered. The mouth is situated in the under part, and is armed with five strong and sharpened teeth. The animal can move from place to place by means of its contractile tubular feet and its spines; but its movements are slow and laborious. So tenacious of life are the Sea-urchins, that the ancients, according to Appian, believed that the body retained life even when cut to pieces.
“If in the sea the mangled parts you cast,
The conscious pieces to their fellows haste;
Again they aptly join, their whole compose,
Move as before, nor life nor vigour lose.”
In Marseilles, and some other towns on the continent, the Sea-urchin is exposed for sale in the markets, as oysters are with us, and is eaten boiled as an egg. The Romans adopted it as food, and dressed it with vinegar, mead, parsley, and mint.
ZOOPHYTES.
Zoophytes were long supposed to hold a middle station between animals and vegetables. Most of them, deprived altogether of the power of locomotion, are fixed by stems that take root in the 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 were placed by Linnæus in two divisions. The stony branches of the first division, which have the general appellation of coral, are full of hollow cells, which are habitations of the animals. The next division consists of such Zoophytes as have softer, fleshy, or horny, stems, and in which the individual polypes are, as it were, amalgamated with their common plant-like habitation.