466 



MUftJAt OP THE MOLLTTSCA* 



Ceassatella, Lamarck. 



Synonyms^ Ptychomya, Ag. Paphia (Lamarck, part) Koissy* 



Tiipe, 0. ponderosa, PL XXL, Fig. 4. C. pulchra. Fig. 259. 



Etymology, crassus, thick. 



Shell solid, vewtricose, attenuated behind, smooth or con- 

 centrically furrowed ; lunule distinct ; ligament internal ; 

 margin smooth or denticulated ; pallial line simple ; hinge- 

 teeth 1.2, striated, in front of cartilage pit; lateral teeth — 1, 

 1— ; adductor impressions deep, rounded ; pedal small, 

 distinct. 



Animal with mantle-lobes united only by the branchial 

 septum ; inhalent margins cirrated ; foot moderate, compressed, 

 triangular grooved; gills smooth, unequal, outer semi-lunar, 

 inner widest in front ; palpi triangular. 



Fig. 259. CrassnteUa pulchra. Sandy Cape, J. B. Jiikes. 

 Animal aa seen on the removal of right valve, and portion of the mantle. 



In CrassatelJa pulchra the animal is like Astarte ; foot lingui- 

 fotm, slightly grooved; palpi short and broad, few-plaited J 

 outer gill narrower in front. 



Distrihution, 34 species. Australia, New Zealand, Philippines, 

 India, West Africa, Canaries, Brazil. 



Fossil, 64 species. Neocomian — . Patagonia, United States, 

 Europe. 



IsoCARDlA, Lamarck. Heart-cockle. 



Etymology, isos, like, cardia, the heart. 

 Type, I. cor. PI. XX., Pig. 3. 



