INVERTEBRATES. 



321 



GENUS AYICULOPECTEN, McCoy. 



AviCULOPECTEN VARSOVIENSIS, Sp. HOV. 



View of left valve, Natural size. 



Shell large, suborbicular, hinge-line rather shorter than the great- 

 est breadth of the valves below. Left valve nearly flat, posterior 

 ear short, and forming a rather acute triangle, which is clearly de- 

 fined from the posterior margin below. 



Anterior ear nearly twice as long as the posterior, not so dis- 

 tinctly angular in outline, the outer margin curving into a deep in- 

 dentation where it joins the lateral border of the shell. Both ears 

 show traces of raised lines or costee, corresponding to those on the 

 body of the shell, and on the anterior ear, faint transverse lines of 

 growth are visible. 



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