OYSTERS, PECTENS, ETC. 



225 



Though mainly small, or of ordinary size, a few Bi- 

 valves are very large. At St. Sulpice, Paris, the valves 

 of a Tridacna, two feet across, are used as vessels for 

 the holy water. The Tridacna lives on coral reefs in 

 the Pacific and Indian Oceans. 



Fig. 430. — Pecten. From Cape Ann Fig. 431. — Mytilus. Both 

 southward. shores of the Atlantic. 



Fig. 432. — Avicula. Fig. 433. — Leda. Fig. 434. — Cardicum. 

 Reduced. Mediterranean. New England. Reduced. New England. 



Oysters, Pectens, Mussels, Pearl Oysters, etc. 



Oysters are more highly prized for food than any 

 other mollusk. They occur in the greatest quantities 



NAT. HIST. AN. — 1 5 



