152 THE HON. PAUL A. METUUEN OX [Feb. 1, 



The maxillula consists of a branchial appendage, a palp, and 

 three biting processes. The branchial plate is provided with 

 twenty-eight plumose rays. The palp is two-jointed ; the distal 

 joint bears five smooth bristles, and the proximal joint one short 

 and six long bristles, also smooth. The third biting process 

 carries terminally two simple bristles and two large and two 

 smaller foliaceous setae ; subterminally there are three plumose 

 bristles and a short smooth one. The second biting process 

 carries terminally nine bristles, some simple, some plumose, 

 and two foliaceous seta?. The first biting process is provided 

 with seven bristles, some of which are simple, the others plumose, 

 and in addition three foliaceous setse. 



The maxilla is precisely similar to that of Eurycypris pubera 

 figured by Olaus except for the presence of an inconspicuous 

 group of hairs midway between the endopodite and the biting 

 process. The clasping organ attached to this appendage in the 

 male consists of a straight proximal and a curved terminal 

 segment ; on the inner side and situated at the distal base of 

 the former piece are two spines, one considerably larger than 

 the other, and the terminal segment ends in a sharp spine. 

 The structure of this clasping organ is different on each side ; 

 on one side the proximal joint is shorter, and the distal joint 

 which is sharply recurved is slenderer than is the case in the 

 opposed portion. On the other side the distal joint is stout 

 and sharply recurved. 



The fourth post-oral limb resembles that of the subgenus 

 Eurycypris in having the second and third segments fused, the 

 internal border of the first joint bearing groups of short bristles 

 which appear to spring from peculiar chitinous thickenings. 

 The terminal serrated claw is somewhat longer than the fused 

 second and third joints, and at its base springs a short serrated 

 spine with a V-shaped base. 



The fifth post-oral limb, the cleaning-foot, closely resembles 

 that of Eurycypris pubera. 



The caudal rami are a pair of slender, slightly curved rods, 

 each carrying terminally a serrated seta which is twice as long 

 as the outer seta inserted just proximal to its base ; this latter is 

 also serrated. They resemble closely those of Eurycypris pubera. 

 The copulatory organ of the male resembles in general shape 

 that of Cyprinoius incongruens described by Miiller. The 

 outer branch of the outer process is foot-shaped, the inner 

 branch being in the form of a curved spine ; the outer border 

 has a large projection to receive the coils of the vas deferens. 



Locality. I obtained a great number of specimens in the 

 littoral water of a small reed -pan near Chrissie and found two 

 or three specimens in Lake Chrissie itself. 



Remarks. — This species is remarkable in the peculiar shape 

 of the shell and especially in the presence of the remarkable 

 spinous processes which have been described. 



The large size of this species is also to be noted. The 



