49 



DIVISION VI. Valves slightly striated, lower valve turning up at its sides, 

 and the cartilage of the hinge placed in a deep, narrow groove. 



Scientific name. Locality. Scientific name. Locality. 



Spondyloidea, Indian Ocean. Ovalis, 



DIVISION VII. Valves coarse and rugged, and not comprehended in the 



former divisions. 



Denticulata, Cape of Good Hope. Edulis, British and other seas. 



