DESCRIPTION OF SPECIES 



355 



with a double row of modified spines (Fig. 22 c) ; the inner margins of the carpus, 

 merus and ischium are fringed with a dense mass of short hairs. The last thoracic 

 appendage (Fig. 22 e) is smaller than the rest and is similar in the two sexes. 



-— 6. — 



Fig. 22. Serolis aspera, n.sp. 

 a, right mandible : x 14. b, second thoracic appendage of (J : x 14. c, third thoracic appendage of adult ^ : 

 X 14. <^, fourth thoracic appendage : x 14. e, last thoracic appendage of cj, propodus and dactylus missing: 

 X 14. 



The protopodite of the first three pairs of pleopods is somewhat triangular in shape, 

 with the produced angle bearing three plumose setae on the first, and two on each of the 

 second and third pleopods. The appendix masculina on the second pleopod of the male 

 reaches about two-thirds of the way towards the apex of the terminal segment. The 

 sutures of the exopod of the fourth and fifth pleopods are almost transverse. 



The uropoda do not extend to the tip of the terminal segment ; the protopodite has 

 its inner angle produced into a long spinous process and the exopod is about two- 

 thirds the length of the endopod. Plumose setae are present on the outer margin and 

 rounded distal extremity of both the exopod and endopod, and their inner margins are 

 fringed with delicate setae. 



Distribution. South Georgia. 



This species very closely resembles .S. pagenstecheri, Pfeffer, but differs from it in the 

 following points : 



(i) The most important difference is that in S. aspera the terga of the sixth and seventh 

 thoracic somites are fused together and with the first abdominal segment for a short 

 distance on either side of the median dorsal line. In S. pagenstecheri the suture between 



