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/ul family ; consisting of such shells only, as have three 

 primary teeth on each valve, the lateral ones diver- 

 gent to the summit. Ligament external, covering the 

 escutcheon. This genus is not in form easily distin- 

 guished from the G. Cytheria, though generally more 

 transverse than orbicular; the hinge however marks 

 the difference most clearly. They are marine shells, 

 free, regular, and beautifully varied in their designs 

 and coloring; they inhabit the sandy shores, buried to 

 a small depth below the surface, and are particularly 

 numerous in warm climates. 



Internal Margin of the Valves crenated, or dentated. 



Shells with lamellar Stria. 

 Venus puerpera Venus verrucosa 



. ••• reticulata rugosa 



pygmaea • casina 



• • •• corbis crebriscula 



crenulata plicata 



discina cancellata 



Venus subrostrata. 



Without lamellar Stria. 

 Venus granulata Venus pectorina 



