22 
BULLETII^ 112, UNITED STATES NATIONAL MUSEUM. 
MODIOLUS RECTUS Conrad, 1837. 
Journ. Acad. Nat. Sci. Phila., vol. 7, p. 243, pi. 19, fig. 1. 
Bolinas Bay, California, to Magdalena Bay, Lower California. 
MODIOLUS FLABELLATUS Gould, 1850. 
Boston .lourn. Nat. Hist., vol. 3, p. 343; Rep. U. S. Expl. Exp. Moll., p. 453, 
fig. 561. 
Vancouver Island to San Diego, California. 
MODIOLUS CAPAX Conrad, 1837. 
Journ. Acad. Nut. Sci. Phila., vol. 7, p. 242 ; Conch. Icon. Modiola, pi. 3, 
fig. 11. 
Santa Barbara, California, to Payta, Peru. 
MODIOLUS FORNICATUS Carpenter, 1864. 
Suppl. Rep. Brit. Assoc., p. 643; Ann. Mag. Nat. Hist, ser. 3, vol. 15, p. J78. 
Trinidad to San Pedro and Cortez Bank, California. 
MODIOLUS (POLITUS Verrill, 1880, var.?) PALLIDULUS Dali, 1916. 
Proc. U. S. Nat. Mus., vol. 52, p. 404. 
Oif Bodega Head, California, and south to Cerros Island, Lower California, 
in deep water. 
Subgenus Gregariella Monterosato, 1883. 
GREGARIELLA OPIFEX Say, 1825. - {/■ 
Journ. Acad. Nat. Sci. Phila., vol. 4, p. 369. pi. 19, fig. 2. 
Santa Barbara, California, to Gulf of California. 
Subgenus Brachydontes Swainson, 1840. 
BRACHYDONTES DEMISSUS Diliwyn, 1817. 
Descr. Cat. Rec. Shells, vol, 1, p. 314 ; Journ. Acad. Nat. Sci. Phila., vol. 7, 
pi. 20, tig. 7. 
Imported with “ seed ” oysters from the Atlantic coast, San Francisco 
Bay, on oyster beds. 
Genus BOTULA Morch, 1853. 
Subgenus Adula H. and A. Adanrs, 1857. 
ADULA DIEGENSIS Dail, 1911. . (Plate 1, figs. 1, 3.) 
Nautilus, vol. 24, No. 10, p. 110; vol. 30, No. 1, p. 2. 
San Francisco Bay to Cape San Lucas. 
ADULA FALCATA Gould, 1851. 
Proc. Boston Soc. Nat. Hist., vol. 4, p. 92; Mex. and Cal. Shells, pi. 6, 
tig. 9. 
Coos Bay, Oregon, to San Diego, California. 
ADULA CALIFORNIENSIS Philippi. 1847. 
Zeitschr. Mai., p. 113 ; Conch. Cab., ed. 2, Litliophaga, pi. 5, fig. 19. 
Vancouver Island to San Diego, California. North Japan. 
Genus DACRYDIUM Torell, 1859. 
DACRYDIUM PACIFICUM Dali, 1916. 
Proc. U. S. Nat. Mus., vol. 52, No. 2183, p. 405. 
Bering Sea, 1401 fathoms. 
