154 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



vicinity of Yes Bay, Behm Canal, 39-45 fathoms, and Kasaan Bay, 

 Prince of Wales Island, 42-47 fathoms, Albatross, and 22 miles north- 

 west of Wrangell, J. S. Ligon (Rathbun, 1925). 



British Columbia: near Nass Harbour, D. C. G. MacKay (Mac- 

 Kay), Victoria, Vancouver Island, C. G. Newcombe (Newcombe) ; 

 north arm of Burrard Inlet, 15 fathoms (Taylor). 



Washington: Griffin Bay, near Friday Harbor, San Juan Islands, 

 60 meters (Queen, as Chionoecetes tanneri). Georgia Strait, N of Orcas 

 Island, 34-35 fathoms; Hale Passage, Lummi Island, 12-19 fathoms; 

 ENE of Vendovi Island, mouth of Bellingham Bay, 15-17 fathoms; 

 East Sound, Orcas Island, 17-18 fathoms; Lopez Sound, San Juan 

 Islands, 28 fathoms; Mission Bar, 2 miles S of Tulalip Bay, 5-13 

 fathoms; off Meadow Point, Seattle, 30-100 fathoms; Carr Inlet N of 

 Raft Island, 28-15 fathoms; off Point Jefferson, opposite Seattle, 136-155 

 fathoms; Port Madison, 43-34 fathoms; the above all taken by the 

 Onchorhynchus (Slipp, 1952). 



Atlantic analogue: None. An eastern Pacific boreal species having 

 as its western Pacific cognate Chionoecetes opilio elongatus Rathbun. 

 (See Remarks below) 



Diagnosis: Carapace tuberculate and spinate, broader than long, 

 branchial regions depressed, lateral margins exposed, scalloped. Meri of 

 ambulatory legs dilated, spinulous. Pterygostomian spines few, last 

 three or four large. Exorbital tooth strongly incurving. Seventh seg- 

 ment of male abdomen weakly inserted into sixth. Male first pleopod 

 strongly reflexed at tip ; about three dozen filaments arranged in two or 

 three rows along convex margin ; about eight irregularly placed in the 

 opposite concavity. 



Description: Branchial regions more depressed than in Chionoecetes 

 opilio, and in consequence the width greater; the width exceeding the 

 length, in C. opilio the width subequal to the length. Inclined sub- 

 triangular facet of the anterior branchial region steeper, higher and 

 shorter than in C. opilio ; highest point marked by a spine, instead of a 

 tubercle; no dorsal spines in C. opilio, that is, none above those in the 

 submarginal row. In C. bairdi the last (posterior) three or four spines 

 of the pterygostomian-branchial row notably enlarged ; also the outer- 

 most of the prominences in the transverse branchial row spinous or 

 spinulous. The whole animal rougher than in C. opilio. Carapace nar- 

 rower across the orbits, outer orbital teeth bent inward more; median 

 emargination of the front wider and the teeth narrower and with less 



