BIVALVES. CHAMA. 



49 



dyli), to affix themselves to any extraneous substance 

 which accident may throw in their way. They often 

 adhere to rocks, stones, and various shells; but, in many 

 instances, they seem to have a preference for some par- 

 ticular genus of shells J for the 0. arcinella is most com- 

 monly found affixed to that species of Murex called the 

 thorny woodcock ; however, it retains a partiality for 

 others of the murices, especially those often known under 

 the name of triplices. 



Tlie American, Indian, and Atlantic Oceans; and the 

 Mediterranean, Caspian, and Adriatic Seas, produce in- 

 finite varieties of this genus. 



The C. foliacea is found fossil in Campania. 



CHAMA.— Clam. 



A. — Closed. 



*CoY.— Fool's Cap. 

 Moltkiana — Moltkian's. 

 Hippopus — Beards Paw. 

 Antiquata — Antiquated. 

 Trapezia — Trapeziform. 

 Semiorbiculata — Suhorhicular. 

 Caly culata — Variegated. 

 Cordata — Heart-shaped. 

 Satiata — Obsolete. 

 Oblonga — Oblong. 

 Lazarus — Jagged. 

 G ryphoides — Gryphus. 



Bicornis — Horned. 

 Arcinella — Hedge-Hog. 

 C oncamerata — Cham bered. 

 Macerophylla — Fir-apple. 

 Foliacea — Leafy. 

 Arata — Furrowed. 

 Fusca — Brown. 

 Citrea — Citron. 

 Thaca — Burrower. 

 Rugosa — Rugged. 

 G r y phica — Griffin . 

 C or alliophaga — Coral. 



B. — Gaping. 

 Gigas — Furbelowed Clamp, Giant Clam. 



