24 RECENT BIVALVE MOLLUSKS 



Section Tridonta Schumacher, 1817. 



Astarte rollandi Bernardi, 1858. 



PribiloiT and Aleutian Islands to Prince William Sound, 



Alaska. Also Kamchatka. 

 Astarte rollandi var. loxia Dall. 1903. 



Semidi Islands, Alaska. 

 Astarte arctica Gray, 1824. 



Circumboreal. Arctic and Bering Sea and the Aleutian 



Islands. 

 Astarte borealis Schumacher, 1817. 



Polar and Bering Seas, North Japan, and eastward to 



Prince William Sound, Alaska. 

 Astarte alaskensis Dall, 1903. 



Southern Bering Sea, the Aleutians and south to Puget 



Sound. 

 Astarte compacta Carpenter, 1865. 



Puget Sound. 

 Astarte fabula Reeve, 1855. 



Circumboreal. Arctic Sea and south in Bering Sea to 



Nunivak Island. 

 Astarte bennettii Dall, 1903. 



Polar Sea at Bennett Island, and south in Bering Sea to 



Nunivak Island. 

 Astarte vernicosa Dall, 1903. 



Arctic and Bering Seas. Attn to Atka Islands in the 



Aleutian chain. 



Section Rictocyma Dall, 1872. 



Astarte esquimalti Baird, 1863. 



Aleutian Islands to Puget Sound. 



Genus Bernardina Dall, 1910. 



Bernardina bakeri Dall, 1910. 

 Coronado Islands. 



Family Crassatellitidss 

 Genus Crassatellites Kruger, 1823. 



Crassatellites fluctuatus Carpenter, 1864. 

 Santa Barbara Islands, Cal. 



Genus Crassinella Guppy, 1875. 



Crassinella branneri Arnold, 1903. 



San Diego. Cal.. to Panama. Pleistocene of San Pedro, 

 Cal. 



