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POPULAR CONCHOLOGY. 



of the world ; the genus includes many rare and beautiful 

 foreign species, of various forms, besides several British. 



Philippi has Schizodesma, Spisula and Mulinia of Gray, 

 as subgenera. 



Cardilia. Deshayes. — Shell oblong, longitudinally 

 heart-shaped; ventricose, with prominent 

 bosses ; hinge with a small cardinal tooth, and 

 a pit at the side; a spoon-shaped projection 

 receives the ligament, which is internal. 

 Animal unknown. 



Deshayes formed this genus for Isocardia 

 Semisulcata and a small fossil shell. The 

 recent species is found on the north coast of 

 New Holland, and the Straits of Malacca. 



Donacilla. Lam. (Mesodesma Desk.) — Shell thick, 

 ovate, transverse or 

 triangular, equi- 

 valve, rather com- 

 pressed and gene- 

 rally closed ; the 

 hinge has two thick 

 lateral teeth in each 

 valve, and between 

 these is situated a 

 deep spoon-shaped 

 cavity for the liga- 

 ment ; the mantle impression has a sinus more or less deep. 

 Animal having the lobes of the mantle connected two 

 thirds of their length, and prolonged behind into two short 

 tubes ; the foot compressed ; the gills short, united behind, 

 the outer pair smaller than the inner pair. — 10 species; 

 also fossil. 



The type is D. (Amphidesma) donacilla. Lam. 



