466 



MANUAL OF THE MOf.LUSCl, 



Crassatella, Lamarck. 



Sijnovyms, Ptycliomya, Ag. Paphia (Lamarck, part) K()i8py. 



Tijpe, C. ponderosa, PI. XXL, Fig. 4. C. pulchra, Fig. 259 



Etymology, crassus, thick. 



Shell solid, veotricose, 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. Crassafella pulchra. Sandy Cape, J. B. Jukes. 

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



In Crassatella pulchra the animal is like Astarfe ; foot lingui- 

 form, slightly grooved ; palpi short and broad, few-plaited ; 

 outer gill narrower in front. 



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

 India, West Africa, Canaries, Brazil. 



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

 Europe. 



IsocARDiA, Lamarck. Heart-cockle. 



Etymology, isos, like, cardia, the heart. 

 Type, l" cor. PI XX., Fig. 3. 



