of the Pacific Shores of North America, 447 



tropics must swarm with Crustacea of the higher orders, the 

 species of which are as yet entirely undetermined. With- 

 out, therefore, attempting to generalize upon so imperfect 

 data, we may notice a few facts with regard to the character 

 of the Crustacean fauna, which are so prominently marked 

 that they will be but little affected by future discoveries. 



The tribe Oxyrhyncha is very numerously represented in 

 the rocky fiords of the upper coast, and a predominance of 

 deep-water forms may be observed, the genera of which are 

 mostly peculiar to this region. The restricted genus Cancer 

 (Platycarcinus, M. Edw.) is remarkably well represented 

 here, by four species, very abundant in individuals, and 

 which are in fact the most common crabs known. On the 

 other hand, with the exception of a single species of Ozius, 

 no other examples of the Cancrinea, elsewhere so numerous, 

 have yet occurred ; and it is indeed singular that the sandy 

 shores of California, so well adapted to Lupa and its allies, 

 should have as yet furnished no species of the Portunidce. 

 In this point a striking difference is shown between the 

 marine fauna of this and the eastern coast, where such 

 forms are abundantly distributed. 



The chief and most noticeable feature, however, which 

 at once gives a peculiar character to the Decapoda of the 

 Northwestern coast, is the remarkable development of the 

 Lithodina. But few species of the rare and curious crabs 

 of this family, all denizens of deep water, were until recently 

 known, one of which (the only one described in the " His- 

 toire Naturelle des Crustaces,") is found in the North Atlan- 

 tic, one in the Antarctic Ocean, and two in the seas of 

 Japan and Kamtschatka. Within the past ten years, how- 

 ever, no less than nine additional species have come to light, 

 nearly all of which were found on the shores of California, 

 Oregon, and Russian America. Among these are some 

 gigantic and representative forms which tend greatly to 

 enlarge our views of the extent, importance, and relations of 

 the group. For our knowledge of these interesting Crusta- 

 ceans, we are chiefly indebted to Brandt of St. Petersburg. 



