NORTHWEST COAST MARINE SHELLBEARING MOLEUSKS. 23 



Genus LITHOPHAGA Bo'ten, 1798. 



Section DIBERUS Dall, 1898. 

 LITHOPHAGA PLUMULA Hanley. 1844. 



Proe. Zool. Sue., p. 17 ; Descr. Cat., p. 239, pi. 24, fig. 23. 

 Monterey, California, to Patagonia. Also Atlantic. 



Section LABIS Dall, 1916. 

 LITHOPHAGA ATTENUATA Deshaycs, 1836. 



Anira. s. Vert., ed. 2, vol. 7, p. 28. — Philippi, Abb. u. Beschr., vol. 2, p. 148, 



pi. 1, fig. G. 

 Monterey to Patagonia. 



Section MYOFORCEPS Fischer, 1886. 



LITHOPHAGA ARISTATA Dillwyn, 1817. 



Descr. Cat. Kec. She" Is, vol. 1, p. 303.— Wood, Index Test., pi. 12, fig. S, 1S25. 

 La Jolla, San Diego County, California, to Peru. Also Atlantic. 



Genus MUSCULUS Bclten, 1798. 



MUSCULUS NIGER Gray, 1824. 



App. Parry's Voy., p. 244; Voy. de la Recherche, pi. 17, fig. 1. 

 Circumboreal. Arctic Ocean to Oregon. 



MUSCULUS NIGER OBESUS Dal!, 1916. 



Proc. U. S. Nat. Mus., vol. 52, p. 405. 

 Arctic Ocean to Cape Flattery. 



MUSCULUS PROTRACTUS Dall, 1916. 



Proc. U. S. Nat. Mus., vol. 52, p. 405. 

 Nunivak Island, Bering Sea, to Monterey. 



MUSCULUS OLIVACEUS Dal!, 1916. 



Proc. U. S. Nat. Mus., vol. 52, p. 405. 

 Bering Sea to Catalina Island, California. 



MUSCULUS IMPRESSUS Dall, 1907. (Plate 3, figs. 6, 7.) 



Smithsonian Misc. Coll., vol. 50, No. 1727, p. 172. 

 Petrel Bank, Bering Sea. 



MUSCULUS TAYLORI Dall, 1897. 



Bull. Nat. Hist. Soc. Brit. Col., No. 2, p. 5, pi. 1, figs. 17, 18. 

 Victoria, Vancouver Island. 



MUSCULUS SUBSTRIATUS Gray, 1824. 



App. 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. 



