NORTHWEST COAST MARINE SHELLBEARING MOLLUSKS. 51 



SILIQUA MEDIA Gray, 1839. 



Zool. Beechey's Voy., p. 153, pi. 44, fig. 2. 



Arctic Ocean and south to the Okhotsk Sea, Bering Sea, and eastward to 

 Cooks Inlet, Alaska. 



SILIQUA PATULA Dixon, 1788. 



Dixon's Voy., p. 355, fig. 2. 



The Okhotsk Sea, the southern border of Bering Sea and eastward to 

 Sitka, Alaska. 



SILIQUA PATULA ALTA Broderip and Sowerby, 1829. 



Zool. Journ., vol. 4, p. 362. 



Bering Strait, south to Unalaska and eastward to Kodiak Island, Alaska. 



SILIQUA PATULA NUTTALLII Conrad, 1837. 



Journ. Acad. Nat. Sci. Phila., vol. 7, p. 232, pi. 17, fig. 9. 

 Lituya Bay, Alaska, and south to Monterey, California. 



Superfamily MACTRACEA. 

 Family MACTRIDAE. 



Genus ANATINA Schumacher, 1817. 



ANATINA UNDULATA Gonld, 1851. 



Proc. Boston Soc. Nat. Hist., vol. 4, p. 89; Journal, vol. 4, pi. 15, fig. 7. 

 San Pedro, California, to Panama. 



Genus MACTRA Linnaeus, 1758. 



Subgenus Mactrotoma Dall, 1S94. 

 MACTROTOMA DOLABRIFORMIS Conrad, 1867. 



Amer. Journ. Conch., vol. 3, p. 193; Nautilus, vol. 7. No. 12, p. 138, pi. 5, 



fig. 1. 

 Lobitas, California, to Topolobampo, Mexico. 



MACTROTOMA CALIFORNICA Conrad, 1837. 



Journ. Acad. Nat. Sci. Phila., vol. 7, p. 340, pi. 18, fig. 12. 

 Neah Bay, Washington, to San Diego, California. 



MACTROTOMA NASUTA Gould, 1851. 



Proc. Boston Soc. Nat. Hist., vol. 4, p. 88. 

 San Diego, California. (West Colomhia?) 



Genus SPISULA Gray, 1838. 



Subgenus Hemimactra Swaihson, 1840. 



Section MACTROMERIS Conrad, 1868. 



HEMIMACTRA (POLYNYMA Stimpson, var.) ALASKANA Dall, 1894. 



Nautilus, vol. S, No. 4, ]>. 40; Zool. Beechey's Voy. Moll., p. 154, pi. 44, fig. 8. 

 Arctic Ocean at Capo Lisburne, south to Bering Sea and the Aleutians and 



eastward to Puget Sound. North Japan, the Kuril Islands and the 



Okhotsk Sea (Schrenck). 



