CONCHIFERA OR BIVALVES. 71 



22. Corbula. — Shell regular, inequivalve, 

 and inequilateral, scarcely gaping ; 

 one cardinal spoon-shaped tooth in 

 each valve, but no lateral; ligament 

 interior. Animal unknown. — 9 

 species recent, 1 of which is also 

 fossil, and 10 fossil only. 



These small shells are met with in the seas 

 of New Holland, China, &c, and the European 

 seas ; one fine species is brought from South 

 America; some of them are found in the in- 

 terior of stones, &c, and M. Dorbigny states 

 that some species live in fresh waters. 



23. Pandora. — Shell regular, oblong, valves 

 unequal and inequila- 

 teral, the upper one 

 flat, and the lower con- 

 vex ; an obtuse, ob- 

 long tooth in one valve, and a cavity in the 

 other; ligament internal. Animal, foot large 

 and triangular, — 10 species recent, and 1 

 fossil. 



The Pandora inhabits the sand at a con- 

 siderable depth, and is found principally in the 

 European seas ; it is also met with in the Per- 

 F 4 



