738 THE VOYAGE OF H.M.S. CHALLENGEE. 



joint expanded, though not very widely, the hind margin almost straight, scarcely serrate, 

 the front margin a little convex, fringed with spines, the inner surface carrying a fringe 

 of long plumose setee, the lower margin rounded behind, overlapping the second joint ; 

 the armature of the following joints very similar to that in the preceding pair, but the 

 fourth joint considerably longer and slightly curved ; the fifth joint also much longer, 

 this exceeding the length of the fourth, and the fourth that of the third. 



Fifth Pera^ojwds. — Side-plates not very deep. Branchial vesicles well developed. 

 First joint much broader above than below, with the front margin much shorter than 

 the hinder, convex above, straight below, armed with few spines ; the hind margin very 

 convex, slightly serrate, the lower lobe greatly overlapping the second joint ; the second 

 joint with a distal row of small spines in front ; the next three joints much shorter than 

 in the preceding pair ; the third joint subequal in length to the fourth and also to the 

 fifth, fringed in front with many small spines and some larger at the apex, carrying five 

 spines on the hind margin, and an apical group ; the fourth joint straight, with seven 

 groups of large spines in front, and four of small ones behind ; the fifth joint with eight 

 groups of long slender spines in front, and three of spinules behind ; the finger very 

 slender, straight, longer than half the fifth joint. 



Pleopods. — Coupling spines long and slender, the shafts plumose, the bent apex small, 

 one margin having four, the other three, small retroverted teeth just below the apex. 

 Immediately below the coupling spines, there are some slender acute spines, setiform, 

 plumose. The cleft spines form a series of six ; they are long, especially the lower ones, 

 but the arms of the cleft are short, the acute arm being coarsely serrate on the inner 

 side. The peduncles, as usual, are longest in the first pair, shortest in the third ; the 

 joints of the rami number about twenty-two on the inner, and about twenty-five on the 

 outer, somewhat curved, ramus. 



Uropods. — The peduncles of all three pairs broad and long, those of the first and 

 third pairs reaching slightly beyond those of the second, all of them much longer than 

 the rami, and seemingly all of them carinate and channelled as in the preceding species ; 

 the first two pairs have very numerous spines fringing the edges, those on the inner side 

 being the longer ; they have also along the centre fringes of long setae ; the peduncles of 

 the third pair seem to be almost unarmed ; in each pair the rami are a little unequal, 

 those of the first and second pairs carinate, with many small spines on the edges ; those 

 of the third pair are broader but not longer than those of the two preceding pairs, not 

 carinate, carrying but few spines, with the inner edge of the outer and the outer edge of 

 the inner pectinate, while in the other two pairs the outer edge of each ramus is pectinate. 



Telson very small, very little longer than broad, the convex sides converging to an 

 almost pointed apex. 



Length. — The specimen, in the position figured, measured, from the front of the head 

 to the apex of the third uropods, close upon nine-tenths of an inch. 



