TlilDACNID^E. 



429 



the buffeting of a comparatively shallow and turbulent sea will be poor and stunted." The 

 Clams are generally attached by the upper valve. The animal is edible, and is considered 

 a great, delicacy. About fifty 

 species of Clams are known. 



THE Tridacnidse are easily 

 known by their deeply waved 

 shells, with the indented edges 

 fitting into each other, and the 

 overlapping foliations of the sur- 

 face. Although separated from 

 the true Clams, they are popularly 

 called by the same name. The 

 YELLOW CLAM is represented as 

 it appears when buried in a mass of 

 white madrepores, and is given in 

 this attitude for the purpose of ex- 

 hibiting the interlocking edges and 

 the bold foliations. A well-known 

 species, called from its enormous 

 dimensions the GIANT CLAM ( Tri- 

 dacna gigas), was formerly rare, 

 but is now tolerably plentiful. 

 It attains to a gigantic size, some- 

 times weighing more than five 



hundred pounds, and containing an animal which weighs twenty pounds, and can furnish 

 a pood dinner to nearly as many persons. The natives of the coasts on which it is found 



THORNY CLAM.. Cham Lazarus. 



SPOTTED BEAR'S-FAW CLAM. Hippopus maculdta. 



YELLOW CLA11. -'I rutucnu crocea. 



namely, those of the Indians seas are extremely fond of this creature, and eat it without 

 any cooking, just as we eat oysters. The substance of the shell is extremely thick and 

 solid, and enables it to be used for many ornamental purposes. 



