THE ICELAND CYPRINA - FAMILY CYPRINIDAE. Shell regular, equivalve, oval, valves solid; epidermis thick, dark; ligament prominent, outside; hinge with four large inter locking teeth; umbones oblique; muscle scars two, oval, polished; joined by pallial line; mantle united posteriorly to form two short ciliated siphons, elsewhere free; foot thick, tongue-like; gills un equal, two on each side. A small family of chiefly fossil species.
Genus CYPRINA, Lam.
Characters of the family.
The Iceland. Cyprina (C. Islandica, Linn.) is our sole living representative of a family containing fossils of several genera and over one hundred species. It is found as a fossil in Sicily
and Piedmont; living it ranges from the coasts of Norway and England to Labrador and south to Massachusetts. When alive the clam wears a shaggy coat of brown or black epidermis. It is like the quahog in general form, or a giant Astarte. It is found after storms on New England beaches. Length, 3 to 4 inches.
Another genus is represented by one of the handsomest of bivalve shells, I socardia vulgaris, Rye., remarkable for the spiral development of its beaks.
Habitat.— China.
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