Oyster

a marine bivalve, or shellfish, much used for food. For a general description of the oyster, see article on the CLAM. An oyster may be distinguished from a clam, however, by the fact that the lower side on which the oyster lies is more rounding than the flat upper valve which acts more as a lid. As it does not travel the oyster has no foot like that of the clam and the snail. The oyster, like the mussel, lies in the water with its valves parted slightly. The hinge is near one end, and the water from which the oyster selects its food passes in, not by a siphon tube, but along the curved border and out at the straight border, being impelled by cilia, or waving, hair-like bodies. The young oysters are set afloat and swim a few days. A small shell then begins to develop, and the young oyster attaches itself to some object to which it becomes cemented for life by the bony material of the forming shell. Ordinary oysters are large enough to gather when four years old. Blue-points are ready at three. Oysters fresh from the water are fit to eat at any season, except from June to August. These months are the spawning season during which oyster fishermen desire to leave the oysters to breed. For these reasons it is just as well to heed the common saying that oysters are good only in months containing the letter R.

There are about seventy species of oysters well distributed around the warmer seas. The common European oyster is gathered along the Atlantic from the coasts of Norway and the Baltic to a point as far south as the Mediterranean Sea. About 6,000,000 bushels of oysters are gathered annually in European waters. Half a million bushels of California oysters are gathered on the Pacific coast. The Virginian oyster is the most desirable species for food. When America was first colonized this oyster was found all along the coast from the St. Lawrence to the Gulf of Mexico. With the exception of beds in the Bay of Chaleur and on the coast of Prince Edward Island it has disappeared north of Cape Cod. Oyster fisheries still extend along the Atlantic coast from Cape Cod to Texas, with the center of the industry in Chesapeake Bay.

Oysters are collected with a dredge, the bottom of which is shaped something like a comb. The oysters are torn loose by the teeth. They are caught in a bag which drags behind, and are brought to the surface. The annual oyster catch of the United States is from 20,000,000 to 28,000,000 bushels, worth about fifty cents a bushel at the wharf. The finest oysters are taken off the coast of Maryland and Virginia. Baltimore is the great oyster emporium of America,--the great oyster city of the world.