18a').] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 647 



False Bay, where tbey are found imbedded in a coarse deposit of gravely 

 boulders, and shells that forms a rich ground for marine life. These 

 si»ecies are also found, in less quantity, at La Playa, and dead examples 

 indicate their existence at Todos Santos Bay. 

 Semele rupium Sby. 



Tbis abounds on the rocky ocean beaches, but rarely collected alive. 



Lutricola alta Conr. 



Not plentiful. 

 CSdalina subdiaphana Cpr. 



Bay shores ; abundant. 

 Cooperella scintiUasformis Cpr. 



With the last ; rarer. 

 Cumingia californica Conr. 



La Playa ; abundant in dead bivalves or in holes. Todos Santos Bay. 



Psammobia rubroradiata Nntt. 



Common at False Bay ; apparently rare elsewhere. 



[Also found at Avatcha Bay, Kamchatka, by me. D.] 

 Sanguinolaria Nuttallii Conr. 



Seemingly plentiful by the quantity of dead examples found on bay 

 shores. 

 Tellina Bodegensis Hds. 



Not plentiful 5 San Diego. 

 Tellina Gouldii Hani. 



Abundant ; San Diego Bay. Also Todos Santos Bay. 



Tellina (Moera) variegata Cpr. 



San Diego Bay ; fine. 

 Tellina (Heterodonax) bimaculata Linn^. 



Abundant along the whole coast. 

 Macoma secta Conr. 



Plentiful at times, as also the two following : 

 Macoma indentata Cpr. 

 Macoma inquinata Desh. 

 Donax californicus Conr. 



Abundant on sandy ocean beaches. 



Donax flexuosus Gkl. 



liarely collected ; San Diego. 

 Petricola carditoides Conr. 



San Diego; not numerous; burrows in soft rock the length of its 

 shell. 

 Saxidomus nuttallii Conr. 



Collected for food and rither abundant in places. 



[The distinction between this and the following form is often hardly 

 specific. D,] 

 Saxidomus aratus Gld. 



Found with the above and about equally plentiful. 



