956 THE HON. P. A. METHUEN ON 



claw, is one- third as long as that of pereiopod I., and carries on 

 the posterior margin two small spines. 



In pereiopod IV. the details of the arrangement of the setae 

 differ very slightly. 



In pereiopod V. the third and fourth joints are equal in length 

 to, but broader than, those of the third pereiopod ; the seta 

 arrangement is not exactly similar, but this slight difference is 

 negligible. In Irene examples the penultimate joint of this 

 appendage carries much longer spines on one side than is the case 

 in specimens from the Makapan caves. 



The pleopods are normal ; the basal portion bears two branches 

 and two little coupling-hooks. The longest pleopod is the 

 second. 



Pleopod I. (PI. LI. fig. 13) : basal portion oblong, slender, and 

 devoid of setse, except the two coupling-hooks ; these little 

 structures bear a few tubercles and one slightly hooked at the 

 end. The inner ramus is somewhat longer than the outer ; each 

 ramus consists of thirteen joints which bear long plumose setse. 



Fleoj)od II. : the basal part bears distally on its anterior margin 

 two fairly long spines, which are absent in the other pleopods and 

 appear to be absent altogether in the male. 



Pleopod III. : the number of joints to the rami are two or 

 three less than those of the fii^st pleopod. 



The uropods : the first uropod the longest ; the third ui'opod 

 not qviite so long as the first ; the second uropod about two-thirds, 

 as long as the first. The peduncle of the first uropod long, longer 

 than either ramus, much longer than peduncle of second ; peduncle 

 of second much longer than peduncle of third. Outer ramus of 

 third uropod long, much longer than those of first ; inner ramus 

 minute. Rami of first uropod longer than those of second. 



Uropod I. (PI. LI. fig. 14): peduncle, broadest at the base, 

 bears five spines on posterior margin, and two others close 

 together distally. Outer ramus a trifle shorter than inner, which 

 bears five spines on posterior margin and two larger and four 

 smaller ones at the extremity. The outer ramus with four rows 

 of spines, three in each row, and another row basally of two 

 spines ; distally two larger and two smaller spines. 



Uropod II. (PI. LI. fig. 15) : peduncle fairly stout as compared 

 with that of iiropod I., narrower basally, but broader distally than 

 same ; on posterior margin two spines ; on median ridge {vide fig.) 

 five spines, the most distal being the longest. Inner ramus 

 longer than outer, which carries on posterior margin four spines,, 

 and distally two longer and five shorter spines ; anterior margin 

 has two small spines ; the outer ramus bears posteriorly four 

 spines, two longer and three shorter distally, and eight spines 

 arranged in couples anteriorly. 



Uropod II J. (PL LI. fig. 16) : peduncle about the same breadth 

 as that of uropod II. ; anterior margin bears distally two small 

 spines ; opposite these is seen the inner ramus bearing one small 

 spine, not counting spine it is one-fourth the length of the peduncle. 



