« НазадПродовжити »
like that of a goose, the eyes marked; the head, neck, breast, wing, tails, and feet, formed; the feathers every where perfectly shaped, and blackish coloured; and the feet like those of other water-fowl, to my best remembrance.'
Few subjects seem to have been more circumstantially related, or to rest on better evidence, than the above: so natural to man is credulity, which passes all bounds, where the prodigy of an event takes firm hold of the imagination, and lays the understanding asleep. Such are part of the wild chimeras that have been retailed concerning the origin of the Bernacles; and as these fables once had great celebrity, we have been induced to relate them here, only to show how contagious the errors of science are, and how prone men are to the fascinations of the marvellous. Bernacle geese are not uncommon on many of the nortbern and western coasts of Great Britain in winter; but they are scarce in the south, and are seldom seen except in inclement seasons. They leave our island in February, and retire northward to breed.
3. Pholas, pierce-stone; inhabitant, 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. Before these animals attempt to penetrate stones, they soften them by discharging a quantity of phosphorescent fluid, which decomposes or corrodes the substance as effectually as any chemical solvent, and prepares it for the reception of the shell, which they are enabled to insert in the manner of a screw, the worm being spiral, and toothed: the animal then begins to make an entrance with the larger end of the shell; and thus all possibility of return is cut off. They are always found below bigh-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. The pholas is so called from a Greek word signifying to lurk in cavities.' : The pholas dactylus affords the character of nearly the whole tribe. The very extraordinary powers possessed by these animals of penetrating into solid bodies, when compared with their apparent imbecility, have justly excited the astonishment of philosophers and naturalists 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 they 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. With this soft, yielding instrument, while yet young and small, they work their way into the substance of the stone, and enlarge their apartment as their increasing size renders it necessary. ; ou 1. The seeming unfitness, however, of these animals 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 afterwards hardened round them by degrees. This opinion, however, has been consuted, in a very satisfactory manner, by Dr. Bohads, who observed that many of the pillars of the temple of
best an Bibalbesorgt
A Beautiful objects.
The greater part of these animals are inhabitants of the ocean, but some of them are found in fresh water. They perforate the sand or mud at the bottom. Many of the species are caught for food, and others for the pearls which are formed within their shells. Some few of the species perforate and live in lime. stone, in the same manner as the pholades. '.'
The pearl-bearing mya (m. margaritifera) is found chiefly in the large rivers of northern latitudes. The British islands, especially Ireland, have been considered famous for their fisheries of the mya, and a few pearls of great value have, at different times, been obtained from these sources; but the quality of British specimens is not held in the highest estimation. Some fine pearls, however, were procured from the Shannon in the present year (1821). The river Irt in Cumberland, the Conway in Wales, and the Tay in Scotland, were once noted for their pearlfisheries. Suetonius reports that Cæsar was induced to undertake his British expedition for the sake of our pearls; and, according to Pliny and Tacitus, he brought home a buckler made with Britislı pearl, which he dedicated to, and hung up in the temple of Venus Genetrix; a proper offering to the goddess of love and beauty, who sprung from the sea.
Several species of gapers are used as food both in
species, the It prefers a vater-mark. como
is alisht after the co
Britain and on the Continent, as the mya arenaria, known to the fishermen about Southampton by the whimsical name of Old Maids. These shells reside in the mud or shingle on the shore, and a few inches below the surface. In some parts of England and Ireland they are much used, but, though common in Scotland, they are never sought after. Another species, the mya truncata, is also very common on the coast. It prefers a hard gravelly bottom, in which it lodges near low water-mark. The inhabitants of the northern islands call it Smuoslin, and employ it when boiled as a supper dish; and it is by no means unpalatable. .. 5. Solen, razor-shell; inhabitant, an Ascidia.
Many of the bivalved shell-fishes have the powers of progressive or retrograde motion, by an instrument that has some resemblance to a leg or foot, and called the tongue. But these animals can, at pleasure, make this assume almost every kind of form which their exigencies require. They 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 ascend or descend at pleasure. The instrument, or tongue, by which their motions are performed, is fleshy, cylindrical, and situated near the centre of their body. When necessary, the animals can make the termination of 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 further 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 until the shell totally