DECAPODS 67 



10 miles west of Point Franklin, 13^ fathoms, 3 $ (Point Barrow Expe- 

 dition). 



Off Cape Sabine, 1 2 fathoms, i ? (W. H. Ball). 



15 miles off Cape Krusenstern, 14 fathoms, i ? (W. H. Dall). 



Rakovaya Bay, Avacha Bay, Kamchatka, i ? (Albatross], 



Off Robben Island, east coast of Sakhalin, Okhotsk Sea, 28 fathoms, 

 i ovigerous ? , type (Albatross station 3650). 



The species differs from S. liljeborgii in its lower carapace, shorter (in 

 the ? ) and less ascending rostrum, smaller eyes, shorter spine of antennal 

 scale (in S. liljeborgii the spine extends considerably beyond the blade), 

 longer dactyli of third to fifth pairs of feet, longer abdomen, and stouter 

 sixth segment. From S. spina it differs in the lower carapace and less 

 ascending rostrum, in the lesser advancement of the lower limb of the 

 rostrum, smaller eyes, shorter spine of scale, shorter and broader lobe of 

 third abdominal segment, which is not carinated, longer dactyli of third 

 to fifth pairs of feet (in S. spina the dactylus of the fifth pair is only one 

 third length of propodus). 



SPIRONTOCARIS TRUNCATA Rathbun. 

 Spirontocaris truncata RATHBUN, Proc. U. S. Nat. Mus., xxiv, 894, 1902. 



Allied to S. spina. Median carina extending nearly to the posterior 

 margin of the carapace, convex, and armed with 4 spines. Rostrum sub- 

 triangular, widest at the extremity, about three fifths 

 as long as the carapace, reaching end of second 

 antennular segment, midrib curving upward as in 

 S. spina, upper margin with i spine at its middle, 

 extremity with 7 spines, 2 above and 4 below the 

 midrib. Supraorbital spines 2, equal, large, one ^SKft 

 behind the other but scarcely above it, well sepa- (X6|) ' Station2886 - 

 rated. Anterior margin with 2 spines below the orbit as in S. spina. 



Antennular acicle reaching beyond the anterior margin of the second 

 segment but not so far as the slender spine at the outer angle of that 

 margin ; a small spine at the middle of the anterior margin of the third 

 segment. Antennal acicle tapering, narrow at the end, reaching one 

 third the length of the thick antennular flagellum. Peduncle reaching 

 beyond first segment of antennular peduncle; flagellum two thirds as 

 long as body. 



Maxillipeds reaching end of antennal scale ; first pair of feet to end of 

 antennal peduncle. The propodi of the third, fourth, and fifth pairs are 

 three times as long as their dactyli. 



Margins of first to third abdominal segments entire ; of fourth to sixth 



