BIVALVES — OSTREA. 63 



Division IV. — Parasitical, or attached to other substances. 



Family 1.- — With one valve produced at the summit. 



Scientific Name. Locality. Common Name. 



Cucullata Africa, Arabia, So. Seas • Hooded Oyster • • 



Virginea Virginia • • • • Virginian. • do • • 



Rostrata Mediterranean Beaked • • • • do • • 



Forskalii Coast of Egypt Forskael's • do • • 



Cristata Crested • • do • • 



Sinensis China Chinese • • . do • • 



Family 2. — With the valves nearly equal. 



Orientahs Indian Seas Indian do • • 



Folium Amboyna, West Indies 



Mediterranean FoHated • • do • • 



Plicata W . Indies, Mediterranean, 



Spain Plaited do • • 



Orbicularis Indian Ocean Orbicular • do • • 



Arborea Atlantic & Indian Seas • • Tree do • • 



Senegaleusis .... Senegal Senegal • • do • • 



Family 3. — With the valves strongly plaited longitudinally. 



Crista-galli Indian Ocean, China • • • ■ Cock's comb do • . 



Hyotis Horned do •• 



Frons West Indies Crested • • • • do • • 



Division V. — With the hinge composed of transverse furrows in a 

 straight line. 



*Crenatula Red Sea ^ Crenated • • do 



Semiaurita Mediterranean Half-eared do 



Penia East &West lndies,China Oblong • • • do 



Isognomon Amboyna Long-hinged do 



Ephippium Tranquebar, Africa Saddle • • • • do 



Alata West Indies Winged • • • do 



Picta Red Sea Painted •••. do 



Legumen Nicobar Isles Pod-shaped do 



