ISrOKTHWEST COAST MAEINE SHELLBEARING MOLLUSKS. 163 
Subgenus Ianacus Mbrch, 1852. 
lANACUS NUMMARIUS Gould, 1846. 
Proc. Boston Soc. Nat. Hist, vol. 2, p. 160; Rep. U. S. Expl. Exp., Moll., 
figs. 480 a-&. 
Plover Bay, Bering Strait, to Mazatlan. 
IANACUS NUMMARIUS FIMBRIATUS Reeve, 1859. 
Conch. Icon., Crepidula, fig. 11. 
Vancouver Island to Gulf of California. 
IANACUS NUMMARIUS PERFORANS Valenciennes, 1846. 
Voy. Venus, Atlas, pi. 24, fig. 9. 
Monterey, California, to Panama, in Pholas borings. 
IANACUS NUMMARIUS GLOTTIDIARUM Dali, 1905. 
Nautilus, vol. 19, No. 3, p. 26. 
San Pedro, California, on Olottidia alMda only. 
Family CALYPTRAEIDAE. 
Genus CRUCIBULUM Schumacher, 1817. 
CRUCIBULUM SPINOSUM Sowerby, 1824. 
Genera of Shells, Calyptraea, figs. 4, 7. 
Trinidad, California, to Tome, Chile, and the Galapagos Islands. 
^ Genus CALYPTRAEA Lamarck, 1799. 
CALYPTRAEA FASTIGIATA Gould, 1846. 
Proc. Boston Soc. Nat. Hist., vol. 2, p. 161 ; Rep. U. S. Expl. Exp., Moll., 
figs. 484 a-6. 
Port Etches, Alaska, to Puget Sound. 
CALYPTRAEA CONTORTA Carpenter, 1865. 
Proc. Cal. Acad. Sci., vol. 3, p. 215. 
Catalina Island, California, to Gulf of California. 
NATICACEA. 
Family NATICIDAE. 
Genus NATICA Scopoli, 1777. 
Subgenus Ckyptonatica Dali, 1892. 
CRYTONATICA CLAUSA Broderip and Sowerby, 1829. (Plate 14, fig. 11.) 
^ool. Journ., vol. 4, p. 372. — Tryon, Man., vol. 8, pi. 9, fig. 65. 
Arctic and Bering Seas, south, in gradually deepening water, to Japan on 
the west and San Diego, California, on the east. 
CRYPTONATICA RUSSA Gould, 1859. 
Proc. Boston Soc. Nat. Hist., vol. 7, p. 43. 
Bering Strait to Forrester Island, Alaska. 
