210 = SHELLS OF SAN PEDRO BAY—WILLIAMSON. 
Scala indianorum Cpr. 
Rare; dead; also fossil. 
Scala occidentalis Nyst. 
San Pedro (W. H. D.) Arnold. New to the fauna. 
Scala retiporosa Cpr. 
One dead shell. (C. T. 8.) 
Subgenus OpaLia Adams, ‘ 
Scala (Opalia) borealis Gld. 
Three or four examples; all fossil? 
Scala (Opalia) crenata Linn. var. crenatoides Cpr. 
A few dead shells. One live shell, Portuguese Bend, found by M. 
Estella Williamson. Alive at Laguna Beach. ‘Abundant off Catalina 
Island, in mud at 16 fathoms.” (W. H. D.) 
Family CERITHIOPSID 4. 
Genus CERITHIOPSIS F. & H. 
Cerithiopsis fortior Cpr. 
‘¢‘Shells too much broken to be sure of identity.” (J. G. C.) 
Cerithiopsis munita Cpr. 
One, dead. ‘Slender form.” (J. G. C.) 
Cerithiopsis purpurea Cpr. 
Three. (C. T. 8.) 
Cerithiopsis tuberculata Mont. 
Very few; dead. 
Family JANTHINID 2. 
Genus JANTHINA Lam. 
Janthina exigua Lamk. (Janthina bifida Totten; J. trifida, of California authors). 
One day in March, last year (1889), a number of these ocean snails 
were washed ashore at Long Beach. This year (1890) not one has been 
found in the bay that I have heard of, but in the early spring months 
some were washed ashore at Catalina Island. 
