Bivalves

Bivalves (Bivalvia) are a group of molluscs that include clams, scallops, oysters, mussels, razor shells, cockles, venus shells, borers, trough shells and many others (some of which have yet to be identified). Bivalves are so named for their paired shells. The shells of a bivalve are made up of two halves that are mirror images of each other and are joined at one edge by a flexible hinge. Each half is asymmetrical and rounded, so that when closed against the other half, forms a domed space near the hinged edge of the shell which accommodates the bulk of the animal's body and narrows towards the edge of the shell that opens.