rium. A remedy that has been recommended is twospoons-full of oil, and one of lemon-juice, (or 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 is sometimes found within the shells. It seems, however, not to have its seat in any thing essential to the Muscle; for, when illness of this kind has been occasioned, some persons have been affected, and others have not, who have eaten at the same time, and at least in equal quantity. THE PEARL MUSCLE The Pearl is a calculus or morbid concretion, which is produced not only in these, but sometimes even in the common oysters, muscles, and other shells. It is found both in the body of the animal, and within 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 until the ensuing season, in order to allow them time to increase their size. * DESCRIPTION. The Pearl Muscle has a flattened and nearly circular 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. SYNONYMS. Mytilus Margaritiferens. Linn.- La Moule Perle. Bosc.—La Moule du Rhin. Unio Margaritifera. Cu vier. 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 stone, of eighteen or twenty pounds weight, tied by a cord to their great toe. Each of them is also furnished with a sack, which 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 themselves drawn up by the men in the boats. The depth of water in which this fishery is carried on, is twenty or thirty yards, and the distance from the shore four or five leagues. When the men are 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, until the season is over. The gains of the adventurers are often small, as the success is very precarious. Great pearls are 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, and often devour the poor adventurers. OF THE PINNA TRIBE*. Few tribes of shell-fish have been more celebrated, even from the remotest periods of antiquity, than these. They are usually found in the sand or mud, in an erect position, with their larger end a little open. In this po *This shell is a bivalve, fragile, upright, gaping at one end, and furnished with a silky byssus or beard. The hinge has no tooth; and the valves are connected on one side nearly through their whole length. The animal is an Ascidia. sition they are firmly fixed, by means of a fine and strong byssus or silk, the fibres of which are agglutinated to the gravel, sand, roots of marine plants, broken shells, and other extraneous substances. The animals of many of the species are used as food, and are in great request for the table. THE SEA-WING *. A bed of these shells was a few years ago discovered in Salcomb Bay, near Kingsbridge, Devonshire, by Col. Montagu, who has given us a very interesting account of them. He states, that they inhabit a gravelly bottom, covered with mud and long sea-weeds, and are only to be approached at particular times, when the sea recedes further than usual. They stand upright, with their broad end about an inch above the surface, and the lower end fixed by a large and strong byssus, which is so firmly attached to. the gravel, that it requires some force to draw them up; and, even when dragged out, the byssus is usually left behind. This beard is composed of numerous fine, silk-like fibres, of a dark purplish brown colour, and two or three inches in length. Many of these shells are caught annually, the animals being accounted a very palatable food; but they require at least five or six hours stewing, in order to render them eatable; if this be properly attended to, they are nearly as good as Scallops, but they are never so tender. * DESCRIPTION. These shells are of all sizes, from an inch to a foot in length. They are rugged, with irregular concen-. tric wrinkles running lengthways from the beak, at the open side, and turning to the hinge, nearly at right angles; some-. times breaking into lamina or plates. The large old shells are of an opaque horn-colour: the small ones are paler, and more diaphanous: all are, more or less, of a changeable green colour, at the bottom of the shell. The valves are connected through their whole length. Montagu. SYNONYM. Pinna ingens. Penn. Montagu. The bank, near Kingsbridge, on which these shells are found, probably increases, so that the water leaves a greater portion of it exposed at every spring tide, than formerly: and, in consequence, great numbers of the animals become an easy prey to crows and gulls. According to Aristotle, the byssus of the ancients was the beard of one of the species of Pinna; but the name seems to have been used indiscriminately by other writers, for any spun material that was esteemed finer or more valuable than wool. Reaumur remarks that the threads of the byssus are as fine and beautiful as silk. The Pinna on the coasts of Italy and Provence, (where it is fished up by means of iron hooks fixed on long poles,) is called the silk-worm of the sea. The stockings and gloves that are manufactured from the byssus which is there collected, are of exquisite fineness, but are too warm for common wear. The Pinna, observes Col. Montagu, has long been celebrated for giving protection to a small species of crab, which was supposed to be of use to it, by giving it notice either of approaching danger, or of the presence of its prey. Respecting this circumstance, many stories have been handed down to us from the earliest times. These, although not wholly unfounded, are mixed with too much fable to be fully credited in this enlightened age. Univalves. OF THE ARGONAUTS IN GENERAL. The animals of the Argonaut tribe, have a near alliance to the Sepiæ or Cuttle-fishes. The shells are spiral, involute, of a white substance, and so thin, as almost to resemble paper. They have each only a single cell, and are not to be confounded with the Chambered or Pearly Nautili, which belong to a different class, and bear very little resemblance to the shells of the present, either in their structure or habits. THE PAPER NAUTILUS, OR ARGONAUT This was the famous Nautilus of the ancients; and, in the early ages of society, it is supposed to have furnished the original idea of navigation. When this little animal 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. These are each furnished at their extremity with an oval membrane, which serves as a sail. The other six arms hang over the sides of the shell, and supply the place of oars and rudder. Oppian, speaking of these animals, says, Two feet they upward raise, and steady keep; In some places, when the sea is not agitated by winds, great numbers of these singular creatures may occasion DESCRIPTION. This shell is six or eight inches in length, of a white or yellowish colour, and but little thicker than paper. It is compressed at the sides, and has a double row of tubercles. The keel or ridge of the shell is slightly toothed on each side. SYNONYMS. Argonauta Argo. Linnæus.-Argonauta Papyracé. Bosc. |