312 MARINE INVERTEBRATES 



these have been introduced from the East by the agency of 

 man, but others no doubt have a natural range through the icy 

 waters north of America and down through the Bering Sea into 

 the Pacific. 



THE CALIFORNIAN PROVINCE 



The Californian province extends from the neighborhood of 

 Vancouver to Cape St. Lucas and has about five hundred species. 

 The northern portion of this area contains some very charac- 

 teristic forms, together with a good mixture of species of more 

 northern habitat; it might properly be regarded as a subprov- 

 ince. From San Diego south to the cape the character of the 

 fauna gradually changes; this coast-line of southern California 

 has also been considered a subregion. The main characteristic 

 of the Californian province is a large development of Haliotis, of 

 the patelliform mollusks, and of the chitons. A very few minutes 

 on any good collecting-beach of California would convince the 

 Eastern conchologist that he had entered upon an entirely new 

 field of research. The most notable genera are Calllostoma, 

 Chlorostoma, Scurria, Acmcea, various genera of the Chitonidce, 

 Purpura, Monoceras, AmpMssa, Norrisia, Olivella, Chorus, and 

 Haliotis. 



THE PANAMIC PROVINCE 



The warmer waters of the Gulf of California belong to the 

 Panamic province, which extends down to South America. This 

 is one of the richest and most interesting faunas in the world. 

 At Panama alone, Mr. C. B. Adams, a noted collector and 

 student of conchology, took upward of four hundred species. 

 About eight hundred species are known in the Gulf of California 

 alone. 



It must be borne in mind that these faunal provinces relate to 

 littoral and shallow-water species, for the present knowledge of 

 deep-water forms is not sufficient to permit of generalization 

 upon their distribution. 



We review here only the conspicuous forms along our own 

 coasts. It may be well to note, however, that in some other 

 parts of the world the development of molluscan life is far 



