Shell inequilateral, sub-orbicular, close, equivalve, sometimes attenuated at one end; two divergent primary teeth, with a cavity at the side; lateral teeth obsolete; ligament internal, inserted in the cavity of the hinge.
Crassatella Kingicola.
C. donacina.
C. sulcata.
C. subradiata.
C. contraria.
C. cuneata.
C. rostrata.
C. glabrata.
C. erycinæa.