90 POPULAR CONCHOLOGY. 



fourth cardinal tooth, which is supposed to 

 distinguish them, is sometimes scarcely visible. 



49. Venus. — Shell equivalve, inequilateral, 

 nearly round or oval, some- 

 times rough on the outside, 

 and every where closely shut. 

 Three cardinal teeth in each 

 valve, sometimes lateral 

 teeth, bosses slightly turned 

 on one side, ligament on the 

 longest side. Animal, foot variable in form, 

 but compressed. — 96 species recent, and 13 

 fossil. 



This genus, which is one of the most beau- 

 tiful amongst the Dimyaria, is found in all parts 

 of the world. The species Venus mercenaria is 

 cut by the North American Indians into beads, 

 of which they construct their wampum or 

 treaty belts, and the shells are also used among 

 them as money, and are made into ornaments 

 for their dresses. Most species serve as food 

 for man. These Mollusca lie buried in the 

 sand, at a short distance from the shore, and 

 are most abundant in hot climates. 



Lamarck's genus Venerieardia is now sup- 



