AMPHIPOD GENUS LEPTOCHEIRUS. 575 



distal angle ; the posterior margins of the 3rd and 4th joints are 

 crenulate, 6-9 crenulations each with a setiile. In the 5th this 

 margin has 5-7 serrations, and 1-3 ciliated hairs inset in the 

 lobe. The 3rd joint carries a dense cluster of ciliated hairs at 

 the anterior distal angle ; and the 5th joint a similar clustei- 

 of feathered setae. Fingers short and curved. In perseopod 3 

 the 4tli joint is slightly longer than the 6th and wider ; 

 5th shorter than 4th ; 6th with groups of short spines. In 

 perseopod 4, the 4th and 6th joints are subequal to each othei- 

 in length ; in one or two of the larger specimens the 6th is 

 slightly the longer; it carries numerous spines and a cluster of 

 very long setse at the distal angle. In perieopod 5, the 4th, 5th, 

 and 6th joints rapidly increase in length ; the 6th is slender and 

 lightly curved, inset on its posterior margin with exceedingly long 

 seise in addition to the spines. 



Pleopods much as in pectinatus, except that the peduncles are 

 shorter in proportion to the rami, about one-third as long, and the 

 outer ramus is only two-thirds the length of the inner ; cleft spines 

 as in pectinatus, 5 in the 2nd pleopod ; coupling-spines with 2 rows 

 of recurved teeth in addition to the recurved apex, 3 teeth in a row 

 in the lower spine, 2 in the upper. 



Uropods (figs. 7 & 8). — There is a marked variation in the 

 length of the ui-opods in different specimens, most noticeable in the 

 3rd pair, connected apparently with the variation in the develop- 

 ment of the last perseopod. In Grube's specimen (fig. 8) the 

 peduncle of uropod 3 is short and broad, shorter than the outer 

 ramus ; inner ramus not quite half the length of the outer. Some 

 of Norman's and Chevreux's specimens are like Grube's type ; in 

 others, the peduncle equals the outer ramus in length and the 

 inner i-amus is nea,rly as long as the outer ; while in the largest 

 specimens with the last perseopods much produced, the peduncle 

 of uropod 3 is longer than the peduncle of uropod 2, and longei- 

 also than the rami, both rami long and slender, inner quite equal 

 to the outer in length. Uropod 1, peduncle shorter than outer 

 ramus, the falciform process of unusual length, reaching almost to 

 the tip of the outer ramus, furnished with 5 spines along the 

 upper curve ; outer ramus a little shorter than the inner, with 

 3 spines and an apical cluster of 5, 3 of which are longer than 

 the others ; inner i-amus with 4 spines and a similar apical group ; 

 these spines are longer and more slender than those of uropod 2. 

 Uropod 2 stoutly built, peduncle short and stout, with the falci- 

 form process equalling the outer ramus in length ; outer ramus 

 shorter than the inner, with 2 spines, inner with 3, each with an 

 apical cluster of 5 strong stout spines (fig. 7). Uropod 3, 

 peduncle produced underneath in a flat laminar expansion ; outei' 

 ramus with a rudimentary 2nd joint carrying 1 long stiff spa rsel}" 

 feathered bi-istle ; the 1st joint has a group of graduated similar 

 bristles almost concealing the terminal joint ; inner ramus slender, 

 tipped with 1 stout spine. This description of uropod 3 applies 

 to all the specimens examined by me. 



Telson (fig. 9) as figui-ed by Ohevreux and Norman : the apical 



41# 



