DECAPODS 133 



A'. No long suberect spine situated on the rostrum ; fewer than four spines 

 on median carina. 

 B. Carapace elongate, about one fifth longer than wide ; blade of an- 

 tennal scale considerably overreaching the spine . . . boreas. 

 B'. Carapace nearly as long as wide ; blade of antennal scale not over- 

 reaching the spine alata. 



SCLEROCRANGON BOREAS (Phipps). 



Cancer boreas Phipps, Voyage North Pole, 190, pi. xii, fig. i, 1774. 

 Crangon Boreas Sabine, in Suppl. to Appendix of Capt. Parry's [First] Voyage, 



p. ccxxxv, 1824. 

 Sclerocrangon boreas SarS, Den Norske Nordhavs-Expedition, xiv, Zoologi, 



Crust., Pt. I, p. 15, 1885.— Holmes, Occas. Papers Calif. Acad. Sci., vil, 



177, 1900, and synonymy. 



Carapace one fifth longer than wide ; three equidistant spines on the 

 dorsal carina ; a tuberculated carina on the branchial regions armed with 

 an anterior spine and one or two obscure teeth. Rostrum triangular, 

 acute; tip horizontal. Antero-lateral angles armed with a spine project- 

 ing forward or a little outward. Blade of antennal scale much produced 

 beyond the spine. Hand twice or more than twice as long as wide ; distal 

 margin obliquely transverse ; spine obliquely longitudinal. The merus has 

 an upper distal spine, the carpus a lower distal spine. 



Abdomen sculptured, the anterior segment with a median dorsal carina 

 which forms a forward projecting tooth on the first segment ; the sixth 

 segment with a double carina, with a sulcus between the ridges; also on 

 each side of the posterior margin a supero-lateral spine. Pleura of the 

 abdominal segments with only one spine each. Telson sulcate ; two pairs 

 of lateral spinules on the terminal half. 



Dimensions. — Male (Alaska), length no mm., length of carapace 32 

 mm., width of carapace at branchial spine 26.4 mm., length of hand 

 13.2 mm., width of hand at inner base of spine 6 mm. 



Harriman Expedition. — Kadiak, 5 fathoms (W. R. Coe) ; Berg Bay, 

 Glacier Bay. 



Distribution. — Arctic Europe and America; Atlantic coast of America 

 southward to Cape Cod ; Alaska (as far south as Killisnoo) ; ' California ' 

 (Ross, Owen); Siberia; Kamchatka (Ross). Depth, 1-44 fathoms. 



Numerous specimens were taken by the Albatross in Bristol Bay and 

 vicinity in 3^-17 fathoms; by the U. S. R. S. Corwin in lat. 66^^ 12' 

 00" N., long. 1680 54/ 00" W., 30 fathoms, lat. 65° 49' 15" N., long. 

 169O 04' 30" W., 26 fathoms, and lat. 71° 02' 00" N., long. 157O 46' 

 00" W., 19 fathoms. 



Killisnoo, Alaska (Northwestern Trading Company). 

 Plover Bay, Siberia, 10-25 fathoms (W. H. Dall). 



