NORTH AMERICAN CONCHOLOGY. 165 



Anatinidae. 



Page. 



22 Anatina papyracea Say. 

 22 Cochlodesma Leanum Couth. 

 Anatina Leana Couth. 



Page. 



"22 Thracia trtmcata Mighels. 

 23 Couthouyi St. 



23 Conradi Couth. 



Pandoridae. 



23 Lyonsia hyalina Conr. i 23 Pandora trilineata Say. 



Osteodtsma hyalina Conr. | 



Corbulidae. 



24 Corbiila contracta Say. 



Myadae. 



24 Glycymeris siliqua Lam. P. arctica Desh. 



Mya siliqua Chemn. 24 Mya truncata Linn. 



24 Panopasa Norvegica Lovln. 24 arenaria Linn. 



Mya Norwigica Spengl. I 



GastrocliaeiBidae. 



24 PetricolapholadiformisZa»2. 



P. fornicata Say. 



24 dactylus Say. 



25 Saxicava arctica Desh. 



Mya arctica L. 



S. distorta Say. 

 25 Saxicava rugosa Lam. 



Mytilus rugosus 0. Fabr. 

 S. distorta Say. 



Pboladidae. 



25 Pholas costata Linn. . I 25 Pholas crispata Linn. 



25 truncata Say. \ 26 Teredo dilatata St. 



GASTEROPODA. 



PTEROPODA. 



Hyaleadae. 



27 Hyalea trispinosa Lesueur. 



Liniacinadae. 



27 Spinalis Gouldii St. (pi. i, fig. 4). 



Clionidae. 



27 Clione borealis Gray Clio borealis Linn. 



PROSOBItAXCHIATA. 



Dentaliadae. 



28 Dentalium striolatam St. I 28 Dentalium occidentale St. 



D. entalis Aligh. D. dentale Gould. 



