DECAPODS 



123 



Dimensions. Length of female (Albatross station 3504) from tip of 

 rostrum to tip of telson 45 mm. ; length of carapace 12 mm. ; length of 

 antennal scale 6 mm. 



Distribution. Bering Sea and Aleutian Islands, 21-91 fathoms, at 

 31 stations of the Albatross; also off Vancouver Island, at i station in 

 24 fathoms; off coast of Kamchatka, 39-100 fathoms, at stations 3643 

 and 3781 ; usually in small numbers. Also taken by Dr. W. H. Dall 

 at 6 stations between Adak and Kadiak, in 9-60 fathoms. Bering Island 

 (N. Grebnitzky). 



CRANGON COMMUNIS Rathbun. 



Crangon communis RATHBUN, The Fur Seals and Fur-Seal Islands of the 

 North Pacific Ocean, Pt. in, 556, 1899. 



Carapace about a third as long as the abdomen; furnished with a 

 median carina on the anterior half, which is armed with two spines, both 

 in front of the middle ; the posterior of these spines is the larger. The 

 rostrum is slender, tapering, ascending, hav- 

 ing a median sulcus, tip rounded, not extend- 

 ing beyond the eyes. A lateral spine nearly 

 in line with the anterior of the median spines ; 

 two large spines on the anterior margin of the 

 carapace, one of which is at the outer angle 

 of the orbit, and the other at the antero-lateral 



angle. FIG. 64. Crangon communis. 9 . 



Station 3611. a. Dorsal view of ante- 



The first segment of the antennular peduncle rior part of carapace <x 2). b. side 



view (X 2). c. Acicle (X 2). d. 



extends beyond the eyes to a distance exceed- chela (x 2$). 

 ing the length of the last two segments; the second segment is about 

 twice as long as the third. The antennal scale is elongate, about two 

 thirds the length of the carapace ; the spine is slender and exceeds the 

 blade. The outer maxillipeds are very slender and extend slightly be- 

 yond the scale. The first pair of feet may not quite reach the scale or 

 may extend beyond it ; the merus has an outer distal spine ; the manus 

 is over three times as long as its average width ; the immovable digit is 

 long and slender, and the dactylus when flexed is obliquely transverse. 

 The sternum has a series of median tubercles. 



The abdomen is smoothly sculptured ; there is a blunt median carina 

 on the third to fifth segments; the first and second segments have a 

 transverse sulcus ; the third and fourth segments have each two trans- 

 verse sulci, which are connected either side of the median carina ; the 

 sixth segment is furnished with two prominent longitudinal carinae, a 

 median sulcus, and a sulcus on the outer side of each carina ; the seventh 



