REPORT ON THE AMPH1PODA. 1193 



spines, the inner surface with a. distinct front margin almost parallel with the hinder, and 

 therefore to some extent concave ; the second joint with one or two little spines on the 

 front lobe; the third joint widened distally, as long as the fourth and rather wider, with 

 very slight spines at two points of the straight hind margin, and stronger spines at three 

 or four points of the convex front ; the fourth joint shorter than the fifth, with three 

 groups of spines on the convex front, three on the straight hinder margin, and some 

 spinules on the hinder slope of the distal margin ; the fifth joint with four groups of 

 spines on each margin ; the finger more than half the length of the fifth joint, broad at 

 the base, much curved, distally acute. 



Second Peraeopods similar to the first, but with the first joint rather shorter and 

 broader, and having spines at five points on the hind margin of the fifth joint. 



Third Perwopods. — The side-plates less deep than the preceding pair. The branchial 

 vesicles similar to the preceding pair, and like them directed forwards. The limb 

 resembling in form the two preceding pairs of peraeopods, but with the third, fourth, 

 and fifth joints longer. The first not longer than in the preceding pair, with a few small 

 spines within the margin at the upper part in front, four spines on the hind margin of the 

 wing, one near the apex of the inner hind margin ; the second joint with two or three 

 small spines on the hind lobe ; the third joint widening distally, not quite so long as the 

 fourth, with small spines at three points of the front margin, and five points of the convex 

 hind margin ; the fourth joint shorter than the fifth, with spines at three points in front 

 and four behind ; the fifth joint with four groups in front and five behind ; the finger 

 not half the length of the fifth joint, broad at the base, distally strongly curved and 

 acute, with two slender setules near the base of the nail, and another a little further off. 



Fourth Per&opods. — The side-plates smaller than the preceding pair, very shallow. 

 The limb like the preceding pair, but with all the joints longer, and the spines stronger ; 

 the first joint with its hind margin less convex and with only two spines. 



Fifth Perseopods similar to the fourth but longer ; the first joint narrowed below. 



Pleopods. — instead of the usual pair of coupling spines on each peduncle, there is 

 here a row of nine, each with an apical pair of hooks, and a second rather larger pair just 

 Delow it ; whether any of the spines on the inner margin of the first joint of the inner 

 ramus are cleft, I have not been able to determine ; the interlocking apparatus of the 

 coupling spines is so strong that the assistance of cleft spines may be unnecessary ; the 

 joints of the rami number from thirteen to fifteen. In Cyrtophium minutum, Haswell, 

 I find a row of six coupling spines. 



Uropods. — The first pair reach beyond the second ; the peduncles equal in length to 

 the inner ramus, which is considerably longer than the outer ; the peduncles and rami 

 have many lateral spines, and the blunt apices of the rami have each a group in which 

 one of the spines is long ; the peduncles of the second pair shorter than the inner, a 

 little longer than the outer, ramus ; the rami armed as in the first pair ; the third 



(ZOOL. CHALL. EXP. PART LXVII. — -1888.) XxX 150 



