I9I3-] Fiiima of the Cliiika Lake : Crustacea Decapoda. 313 



Paulson's figure) and a curious rounded lobe on the external margin of the exopod 

 near its apex. On the second maxillipsde ' (text-fig. ^^a) there is a small epipod, 

 but no exopod. The last two segments of the endopod bear conspicuous .spines ; the 

 ultimate segment is acutely produced at the apex. 



The third maxillipedes (text-fig. 356) reach about to the end of the antennular 

 peduncle and bear both epipod and exopod , the latter reaching the distal end of the 

 antepenultimate segment. The ultimate segment bears a few stout setae at its apex 

 and is a little shorter than the penultimate. 



The first and second peraeopods (text-figs. 35c, d) reach about to the end of the 

 antennal scale, the latter pair being slightly longer than the former. The exopod of 

 the first pair reaches nearly to the end of the ischium ; that of the second pair is a 

 trifle shorter. The ischium is longer than the merus and decidedly shorter than the 

 chela. The palm is about one and a half times the length of the carpus and the 

 fingers are almost or quite one and a half times the length of the palm. On the 

 inner edges of the fingers are numerous forwardly directed spinules, three or four 

 of which are noticeably longer than the others. The spinulation on the lower edges 

 of the .segments varies according to sex ; but in both male and female there are two 

 or three large spinules on the basis. In the female there are a number of large 

 spinules on the inferior margins of the merus, carpus, palm and dactylus; in one 

 specimen in which they appear to be specially well developed there are 6 on the 

 merus, 4 on the carpus, 5 on the palm and 6 on the dactylus. In the male the 

 spinules are smaller and appear to be less numerous. There is always a strong 

 spinule at the upper distal end of the ischium. 



The third peraeopods (text-fig. 35^) reach to the carpus of the second pair ; the 

 exopod extends a little beyond the middle of the ischium. The ischium is the longest 

 segment, its length exceeding that of the two following combined. The propodus 

 is one half the length of the merus, nearly twice the length of the carpus and fully 

 one and a quarter times as long as the dactylus. On the upper edge there are long 

 setae at the distal end of the ischium and on the merus ; on the lower edge there are 

 numerous setae on all the segments and 3 spinules on the ischium, 4 on the merus 

 and I on the carpus. 



The fourth and fifth peraeopods are much reduced and do not reach the anterior 

 margin of the carapace. The fourth legs (text-fig 35/) are remarkable for the large 

 ventral spine borne by the ischium. This spine slopes strongly forwards and, just in 

 advance of its base on the protruding margin of the segment, are two small movable 

 spinules (text-fig. 35^). The apparatus is perhaps used for cleaning the appendages, 

 acting as a comb. The exopod reaches a little beyond the end of the ischium. The 

 merus and carpus are subequal in length, a little longer than the ischium. The dac- 

 tylus is five sevenths the length of the carpus and one sixth longer than the propodus, 



' Paulson's figure of this appendage seems to be wholly erroneous. Owing to faulty dissection he 

 has in one of his preparations confounded the first and second maxillipedes, the exopods of the former 

 appearing as a portion of the latter. 



