48 BIVALVES SPONDYLUS. 



and terminates in a curved and lengthened beak, 

 which in most of the genus has ears on each side. 



The usual colors are orange, red, purple, white, or 

 brown, tM^o of which are often blended in the same shell. 



The Spondyli are met with in the American, Indian, 

 Mediterranean, and other seas, adhering to rocks, corals, 

 &c. in groups, often forming large masses; others are 

 also found attached to shells. 



This genus has been named Spondylus, from the re- 

 semblance which some of its species bear to the head of 

 an artichoke (ajrov^vXog). 



Division I. — Shell armed with spines or ramifications. 



Family 1 — Sharp spines. 



Scientific Name. Locality. Common Name. 



Gaedaropus- • • •- • Amboyna, West Indies- • Thorny red Spon. 



Regius India Royal do • • 



Aurantius Mauritius Orange- • • • do • • 



Citrinus East Indies Yellow • • • • do • • 



Histrix Indian Seas . • ■ Hedgehog .do • • 



Family 2. — Having palmated or foliated ramifications. 



Palmatus • = » Palmated • • do • • 



Spathuliferus Pied do • • 



Ducalis Ducal do • • 



Division II. — Shell unarmed. 



Family I.— Upper valve longitudinally striated. 

 Anacanthus Indian Seas Spineless • ■ do • • 



Family 2. — Valves longitudinally plaited. 

 Plicatus West Indies Plaited do- 



