VANCOUVER ISLAND CRABS. 263 



Bates, F.R.S., who named and described the 

 new and other species ; I append the report he 

 very kindly sent me. 



(The new species of crustaceans, collected on 

 the east side of Vancouver Island, were some of 

 them dredged in from eight to ten fathoms water ; 

 the rest were collected between tidemarks). 



Mr. Spence Bates says, in speaking of the col- 

 lection generally : ' The extremely opposite and 

 varied localities in which many of the species 

 here represented have hitherto been found, 

 suggest the idea that Vancouver Island corres- 

 ponds with the extreme limit between a northern 

 and a tropical fauna. It is only in this way I 

 can account for finding the representatives of 

 tropical species with others that are found only 

 (on the eastern coast of Asia) in the Arctic and, 

 perhaps, North Atlantic Oceans.' That he is 

 quite correct in this assumption I think there can 

 be no doubt ; for not only does it apply to the 

 crustaceans, but with equal force to all the 

 molluscous groups. Several new species of 

 shells, collected at the same time and in the same 

 localities as the crustaceans, which were named 

 and described by Dr. Baird, with appended notes 

 by myself, and published in the Zoological 

 Society's Proceedings for the year 1864, are 



