CONCIIOLOGY. 



O. Braziliana. 

 O. rostralis. 

 O. denticulata. 

 O. cornucopiae. 

 0. doridelia. 

 0. limacella. 

 O. hippopus. 

 O. Adriatica. 

 O. cristata. 

 O. numisma. 

 O. tulipa. 

 O. scabra. 

 0. parasitica. 

 O. spathulata. 

 O. cucullata. 

 O. rubella. 

 O. Brucella. 

 O. labrella. 

 0. radiata. 



O. gibbosa. 

 O. elliptica. 

 O. deformis. 

 0. plicatula^ 

 O. fusca. 

 O. cristagalli. 

 O. virginica. 

 O. excavata. 

 O. simuata. 

 O. tuberculata. 

 O. magaritacea. 

 O. Australis. 

 O. haliotidaja. 

 O. fucorum. 

 O. glaucina. 

 0. turbinata, 

 O. folia. 

 O. hyotis. 

 O. imbricata. 



2. Genus Gnjphxa. 

 Animal. Unknown. 



Shell. More finely lamellated than in the Ostrea, free, or 

 slightly adhering, subequilateral, very inequivalve ; the inferior 

 valve very concave, with a summit more or less recurved in a 

 hook ; the superior opiculiform and much smaller ; hinge toothless ; 

 ligament inserted in an elongated and arcuated cavity ; a single 

 muscular impression. Habitation unknown. One species. ' 



Gryphaea angulata. 



3. Genus Vulsella. 

 Animal. Body elongated and compressed ; mantle much pro- 

 longed posteriorly, and edged with two rows of very close tuber- 

 cular papilla?; a moderately -large abdominal foot, proboscidiform, 

 canaliculated, without byssus ; a very large transversal mouth 

 with well-developed triangular labial appendages ; branchiaB nar- 

 row, very long, and united in nearly all their extent, 

 8=^ ' 



