ALASKAN ISOPODS. 



215 



produced at the outer posterior angle, becoming more and more pointed in the la^-t -I segments. The 

 epimera of the last segment only project beyond the posterior margin of the segment. 



The first segment of the abdomen is entirely concealed by the last thoracic segment. The fifth is 

 narrower than the preceding ones, but longer in the median line. The terminal abdominal segment 

 i- linguiform, rounded posteriorly, with smooth margins furnished with short hairs. 



The uropoda do not exceed in length the terminal abdominal segment. The outer branch is 

 si anew hat narrower and is shorter than the inner, and both branches arc armed with a few short spines 

 along tit iter margins, and with long hairs along the inner margins. 



The first three pairs of legs have the propodus armed with a process, the edge of which is 

 denticulate with six teeth meeting squarely and without interval, forming an unbroken line; the 

 carpus is armed with one inconspicuous spine; the merus has five short blunt spines along the inner 



Fig. 4. — Rocinela propodUUis Richardson, new species, a, Read with antennae, X 3J 



c, right nropod, x 8|; rl. tec of third pair. 11|. 



!', abdomen with uropoda, x 3* 



margin, anil the ischium is furnished with one lung spine at the outer distal angle. The last four 

 pairs of legs are armed with numerous spines. 



Only one specimen, a male, and the type i Xo. L".»-4S V. S. Nat. Mus. ), was taken by the Albatross, 

 at station 4L'll5, Admiralty Inlet, vicinity of Port Townsend, at a depth of 15-26 fathoms. 



This species differs from R. angustata Richardson *, which it closely resembles, in the denticulate 

 process arming the propodus of the first three pairs of legs, with six contiguous teeth meeting squarely 

 along the edge, while in /.'. angustata the propodus is armed with four long spines; in having the 

 merus of these legs armed with five blunt spines instead of four long ones; in having the outer branch 

 of the uropoda a little shorter and narrower than the inner branch instead of almost twice as wide; 

 and in having the frontal process of the head wider and the distance between the eves in front greater 

 than in R. angustata. 



*SeeProc. f s. Nat. Mus., Vol. XXVII, 1904, p. 3S. 



