NORTHWEST COAST MARINE SHELLBEARING MOLLTJSKS. 39 



Superfamily CARDIACEA. 



Family CARDIIDAE. 



Genus CARDIUM Linnaeus. 1758. 



Subgenus Tbachycabdium Morch, 1853. 



TRACHYCARDIUM QUADRAGENARIUM Conrad, 1837. 



Journ. Acad. Nat. Sci. Phila., p. 230, pi. 17, tig. 5. 



Santa Barbara, California, to Todos Santos Bay, Lower California. 



Subgenus Cerastoderma Morch, 1853. 



CERASTODERMA CORBIS Martyn, 1784. 



Figs. Nondescript Shells, table 2, pi. SO; Univ. Gal. Zool. Publ., vol. 14. 



pi. 20, fig. 1. 

 Nunivak, Pribilof, and Commander Islands, Bering Sea, south to Hakodate, 



Japan, and San Diego, California (Lower California?). 



CERASTODERMA CILIATUM Fabricius, 1780. 



Fauna Gronl., p. 410; Binney's Gould's Inv. Mass., p. 140, fig. 150. 

 Circuinboreal. Arctic Ocean and southward to Puget Sound and North 

 Japan. 



CERASTODERMA DECORATUM Grewingk, 1850. 



Verh. Min. Ges. zu St. Petersburg, 1S48-9, p. 274, pi. 4, figs. 3 a-g. 

 Pleistocene of Alaska and British Columbia. Recent? 



CERASTODERMA CALIFORN1ENSE Deshayes, 1841. (Plate 14, fig. 8.) 



Guerin, Mag. de Zool., Moll., pi. 47. 



Arctic Ocean to San Diego, California, North Japan and Okhotsk Sea. 



CERASTODERMA CALIFORNIENSE COMOXENSE Dall, 1900. 

 Proc. U. S. Nat. Mus., vol. 23, No. 1214, p. 390. 

 Pleistocene of Vancouver Island. Recent ? 



CERASTODERMA FUCANUM Dall, 1907. 

 Nautilus, vol. 20, No. 10, p. 112. 

 Southern Bering Sea, off Unimak Island, and south to Monterey, California. 



? Subgenus Ringicardium Fischer, 1887. 



RINGICARDIUM PROCERUM Sowerby, 1833. 



Proc. Zool. Soc, p. 83; Conch. 111. Cardium, tiff. 23. 

 Pleistocene, San Diego. Cerros Island to Payta, Peru. 



Subgenus Fragum Bolten, 1798. 



FRAGUM BIANGULATUM Sowerby, 1829. 



Zool. Journ., vol. 5, pt. 4, p. 367; Conch. 111. Cardium, fig. 2. 

 San Pedro, California, to Panama. 



Subgenus Trigoniocardia Dall, 1900. 



TRIGONIOCARDIA EUDOXIA Dall, 1916. 



Proc. U. S. Nat. Mus., vol. 52, p. 412. 



Catalina Island, California, to Gulf of California. 



