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 Gould, 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 Dali, 1894. 
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. ///y 
MACTROTOMA NASUTA Gould, 1851. 
Proc. Boston Soc. Nat. Hist, vol. 4, p. 88. 
San Diego, California. (West Colombia?) 
Genus SPISULA Gray, 1838. 
Subgenus Hemimactra Swainson, 1840. 
Section MACTROMEEIS Conrad, 1868. 
HEMIMACTRA (POLYNYMA Stimpson, var.) ALASKANA Dali, 1894. ^ JSA.0CJbn.a^ ^ 
Nautilus, vol. 8, No. 4, p. 40 ; Zool. Beechey’s Voy. Moll., p. 154, pi. 44, fig. 8. 
Arctic Ocean at Cape Lisburne, south to Bering Sea and the Aleutians and 
eastward to Puget Sound. North Japan, the Kuril Islands and the 
Okhotsk Sea (Sclirenck). 
