326 DR THOMAS SCOTT ON THE 



decrease in length, as indicated by the formula, which shows approximately the pro- 

 portional lengths of all the joints : 



Proportional lengths of the joints 11 21 7 15 ll 10 9 

 Numbers of the joints 1 2 3 4 5 6 7 



The second joint bears three small teeth on its upper edge, as shown in the drawing 

 (fig. 2). 



AntennjB moderately stout, and armed with an elongated and slightly curved 

 terminal spine and a few moderately long setae. 



Mandibles and maxillae somewhat resembling those of the Lichomolgus mentioned 

 above. 



The first maxillipeds are also somewhat similar to those of the same species. 



The second maxillipeds are each composed of two joints of nearly equal length ; the 

 second joint is narrow at the proximal end, but increases in width towards the distal 

 extremity, which is obliquely truncated ; the external part of the truncated end appears 

 to be slightly hollow, and armed with four short spines, while the inner angle is 

 produced into a stout spiniform tooth (fig. 6). 



The first and second pairs of swimming feet are somewhat similar to those of other 

 species of the Lichomolgidse. In the third pair, the end joint of the outer ramus 

 carries five dagger-shaped spines round the outer margin and apex, and five seta3 on the 

 inner margin. A dagger-shaped spine also springs from the outer distal angles of the 

 first and second joints, while the second has also a seta on its inner edge. The inner 

 ramus has the end joint furnished with three dagger-shaped spines and two set^, while 

 the second joint bears two seise and the first one seta on the inner margin, as shown in 

 the drawing (fig. 9). 



In the fourth pair, the inner ramus is uniarticulate, rather longer than the first joint 

 of the outer ramus, and carries two setse at the apex ; there is also a small but distinct 

 tooth near the middle of the inner margin (fig. 10). 



The fifth pair consist each of a single, elongated, narrow joint which bears two setse 

 at its distal end. 



Abdomen narrow, elongated, the penultimate segment rather shorter than that on 

 either side. Caudal rami short, about equal in length to the last abdominal segment 

 (fig. 12). 



The male differs from the female in being provided with larger second maxilli2)eds, 

 which are each armed with a moderately long and slender terminal claw ; the end joint 

 is also fringed with minute bristles, as shown in the drawing (fig. 7). The genital 

 segment of the abdomen is also considerably enlarged (fig. 13). The length of the 

 female is fully one millimetre, but the male is rather smaller. 



Habitat. — Obtained from Gulf-weed collected by the Scotia in June and July 

 1904, between Stations 499 and 553, St Helena, 15° 57' S., 5° 40' W., to Tuskar Rock, 

 51° 13' N., 7° 20' W. 



(ROY. SOC. EDIN. TUANS., VOL. XLVIII., 572.) 



