HIPPURITES

A genus of extinct MoHusks, supposed to be bivalves, and referred to the extensive group called Rudistes by Lamarck. The principal valve of the present genus is of a sub-cylindrical or elongated conical form, traversed by one or more internal longitudinal ridges, and closed by a small sub-circular discoid valve like an operculum. The Hippurites are characteristic of the rocks of the cretaceous era in the south of France, Spain, Greece, and other countries bordering the Mediterranean. [s. 570]