as well as the extension of the habitat of many species, make the present 

 list desirable. 



Several forms have recently been discovered by the Albatross in deeper 

 water. Most of these, however, have little relationship to the littoral 

 fauna and the deeper water has not been sufficiently explored to warrant a 

 list at the present time. 



We have placed the dividing line between the littoral and the bathybial 

 faunas of this region at 150 fathoms, because all of the genera so far recorded 

 from this depth have representatives in the shallower water — fifteen to 

 fifty fathoms. Some of the littoral gen,era, as Sebastodes, have representa- 

 tives in deeper water, but this is not of general occurrence. 



Cerros island is a convenient and natural southern boundary to this 

 region. South of it few, if any, of the characteristic genera (Sebastodes, genera 

 of Embiotocidae,) of this region are found. A number of southern forms 

 extend further north, but the number has not been materially increased 

 by our explorations at San Diego; on the other hand a large number of 

 northern forms, or representatives of northern forms, which had not been 

 found south of Point Conception, were added to the San Diego fauna. The 

 California fauna has hitherto been divided into a southern and a northern at 

 Point Conception. This division was the result of insufficient exploration, 

 and the results mentioned above have made it evident that no definite 

 boundaries can be assigned for a northern and a southern California fauna. 

 It is quite evident, and readily admitted, that the fauna of California is 

 distinct from the Alaskan fauna, and the latter has been added for conven- 

 ience and comparison only. But four of the species found at San Diego 

 are also found in Alaska. The California fauna is characterized by the 

 abundance of species of Sebastodes, of Cottidse and of Embiotocidae. The last 

 are entirely absent from Alaska, while only a few species of Sebastodes are 

 found here. The boundary between these two regions lies somewhere 

 between Sitka and Puget Sound. No Embiotocidae are found at Sitka. 

 The relative number of species at the principal localities is as follows: 



The whole of Alaska 109 species 



Puget Sound 106 ',' 



San Francisco 155 " 



Monterey 149 " 



Santa Barbara 119 " 



San Pedro 82 " 



San Diego, including Cortes Banks 168 " 



There are known from the entire region 382 species, belonging to 228 



