OF THE NORTHWEST COAST OF AMERICA 33 



Saxidomus giganteus var. brczis Dall, 1916. 



Admiralty Island. Alaska, to Tacoma, Wash. 



Siibfainily \"enerinae 

 Gcinis Chione Megerle, 1811. 



Chione fluctifraga Sowerby, 1853. 



San Pedro, Cal., to the Gulf of California. 

 Chione undatella Sowerby, 1853. 



San Pedro. Cal., and south to Guayaquil. 

 Chione succincta Valenciennes, 1833. 



San Pedro. Cal., to Panama. 



(iCJius \'enus ( L. ) Lamarck, 1799. 



Venus kennicottii Dall, 1871. 



Neeah Pay. A\"ash., to Little River, Mendocino Co., Cal. 



Genus Alarcia H. & A. Adams, 1857. 



Marcia kennerlyi (Cpr.) Reeve, 1863. 



Kadiak Island, Alaska, to Carmel Bay, Cal. 



Section Yenerella Cossmann, 1886. 



Marcia subdiaphana Carpenter, 1864. 



Sannakh Islands, Alaska, to the Santa Barbara Islands, 

 Cal. 



Genus Paphia Bolten, 1798. 



Subgenus Protothaca Dall, 1902. 



Section Callithaca Dall, 1902. 



Protothaca tenerrima Carpenter, 1856. 



Puget Sound to San Ouentin Bay, Lower Cal. 



Section Protothaca s. s. 



Protothaca staminea Conrad, 1837. 



Commander and Aleutian Islands, to Kamchatka and 



North Japan, and to Puget Sound and Socorro Island. 

 Protothaca staminea \ar. staminea Conrad, 1837. 



Crescent City, Cal., to Socorro Island. 

 Protothaca staminea var. ruderata Deshayes, 1853. 



Southern Bering Sea, to Lobitas, Cal. 

 Protothaca staminea var. petitii Deshayes, 1839. 



Aleutian Islands to San Quentin Bay, Lower California. 

 Protothaca staminea var. laciniata Carpenter, 1864. 



L^nalashka, Alaska, to San Diego, Cal. 



