NORTHWEST COAST MARINE SHELLBEARING MOLLUSKS. 
Geims LITHOPHAGA Bo!ten, 1798. 
28 
Section DIBERUS Dali, 1898. 
LITHOPHAGA PLUMULA Hanley, 1844. 
Proc. Zool. Soc., p. 17 ; Descr. Cat., p. 239, pi. 24, fig. 23, 
Monterey, California, to Patagonia. Also Atlantic. 
Section LABIS Dali, 1916, 
LITHOPHAGA ATTENUATA Deshayes, 1836. 
Anim. s. Vert., ed. 2, vol. 7, p. 28. — Philippi, Abb. u. Beschr., vol. 2, p. 148, 
pi. 1, fig. 6. 
Monterey to Patagonia. 
LITHOPHAGA ARISTATA Dillwyn, 1817. 
Descr. Cat. Ilec. Shells, vol. 1, p. 303.— Wood, Index Test, pi. 12, fig. 8, 1825. 
La Jolla, San Diego County, California, to Peru. Also Atlantic. 
MUSCULUS NIGER Gray, 1824. 
App, Parry’s V'oy., p. 244; Voy. de la Recherche, pi. 17, fig. 1. 
Circumboreal. Arctic Ocean to Oregon. ; 
MUSCULUS NIGER OBESUS Dal!, 1916. 
Proc. U. S. Nat. INIus., vol. 52, p. 405. 
Arctic Ocean to Cape Flattery. 
MUSCULUS PROTRACTUS Dali, 1916. 
Proc. U. S. Nat. IMus., vol. 52, p. 405. 
Nunivak Island, Bering Sea, to Monterey. 
MUSCULUS OLIVACEUS Ball, 1916. 
Proc. U. S. Nat. Mus., vol. 52, p. 405. 
Bering Sea to Catalina Island, California. 
MUSCULUS IMPRESSUS Bail, 1907. (Plate 3, figs. 6, 7.) 
Smithsonian Misc. Coll., vol. 50, No. 1727, p. 172, 
Petrel Bank, Bering Sea. 
MUSCULUS TAYLORI Dali, 1897. 
Bull. Nat. Hist. Soc. Brit. Col., No. 2, p. 5, pi. 1, figs. 17, 18. 
Victoria, Vancouver Island. 
MUSCULUS SUBSTRIATUS Gray, 1824. 
x\pp. Parry’s Voy., p. 245 ; Voy. de la Recherche, pi. 17, fig. 3. 
Circumboreal. Arctic Ocean to Puget Sound. 
MUSCULUS CORRUGATUS Stimpson, 1851. 
Shells of N. Engl., p. 12 . — Gould, Inv. Mass., p. 130, fig. 84. 
Circumboreal. Arctic Ocean to Puget Sound. 
MUSCULUS VERNICOSUS Middendorff, 1849. 
Mai. Rossica, vol. 3, p. 20, pi. 11, figs. 25-27. 
Bering Sea to Sitka. Also Okhotsk Sea. 
Section MYOFOIICEPS Fischer, 1886. 
Genus MUSCULUS Bolten, 1798. yxcrh 
