186 SHELLS OF SAN PEDRO BAY—WILLIAMSON. 
Tellina obtusa Cpr. 
Rare; soft parts gone. 
Tellina verbena Cpr. 
A few found by two collectors. (C. 'T.S.) 
Genus G2DALINA Cpr. 
Gidalina subdiaphana Cpr. 
A few living. 
Subgenus COOPERELLA Cpr. 
Gidalina (Cooperella) scintilleformis Cpr. 
One broken shell. (C. T. 8.) 
Genus LUTRICOLA Blainville. 
Lutricola alta Conr. 
A few live shells washed ashore inthe spring; single valves common. 
Genus SEMELE Schumacher. 
Semele californica Adams. (S. flavescens Gld.) 
One young example. (C. T. 8.) 
Semele decisa Conr. | 
Not plentiful. 
Semele pulchra Sby. 
Mrs. Trowbridge reports a live shell washed ashore, after a heavy — 
storm, in San Pedro Bay. (W. H. D.) 
Semele rupium Sby. 
Two or three; dead. 
Genus CUMINGIA Sowerby. 
Cumingia californica Conr. 
Alive at Point Fermin, between the ledges of rock, in company with 
Chitons. 
Genus DONAX Linné. 
Donax californicus Conr. 
This little shell, rich in color-variations, is one of our ‘‘ economic mol- 
lusea;” for it makes a palatable soup. Plentiful at Long Beach. 
Donax flexuosus Gld. 
Not often found living. 
