REPORT ON THE AMPHIPODA. 1095 



inner margin ; the finger nearly as long as the third joint, narrowing very gradually till 

 the apical part, which carries four slender spines on the oblique inner margin, and at the 

 tip no nail but a strong spine, which is long but not nearly so long as the body of the 

 finger, nor so long as a slender spine next to it. 



First Gnaihopods. — Side-plates small, directed forwards, but not covering the base 

 of the lower antennas. The first joint narrow at the neck, extending much beyond the 

 side-plate, with many long setas on the convex hind margin, and others along the surface ; 

 the second joint with a large apical group of spines ; the third joint with the two convex 

 margins converging to a pointed apex, carrying many groups of spines on the surface and 

 along much of the hind margin ; the wrist almost as long as the first joint and distally 

 wider, the long front margin little convex, with a group of spines at the apex, and some 

 spinules elsewhere, the convex serrate hind margin fringed with numerous groups of 

 spines, of which there are several also on the surface and hinder apex ; the hand rather 

 shorter than the wrist, the front margin convex, with six or seven groups of spines in 

 rows on the adjacent surface ; the hind margin much more convex than the front, the 

 major part of it, which may be regarded as the palm, being finely pectinate, the surface 

 immediately adjacent and at a little distance carrying several groups of spines, besides 

 which there are many single spines and spinules at intervals along the margin ; the 

 finger is of great size, in the larger specimen (but not in the female) longer than the 

 hand, and no doubt adapted for impinging against the wrist or to hold fast an object 

 pressed against the wrist ; the dorsal cilium is small, near the base ; the inner margin 

 is cut into seventeen little teeth, resembling spine-teeth, with a hair or cilium adjacent to 

 each, or with few exceptions ; at a little distance from the base of the sharp nail two or 

 three setules are inserted. 



Second Gnaihopods not much longer, though very much broader, than the first pair. 

 The side-plates deeper and much broader than in the preceding segment, broader than 

 deep, the lower margin rather concave in the middle. The first joint almost entirely free 

 from the side-plate, and expanded in a very abnormal manner, more like the first joint of 

 one of the hinder perseopods than like that of a gnathopod ; the breadth is greatest a 

 little way below the narrow neck or point of attachment, from which the upper margin at 

 once spreads out on either side ; the hind margin, which is slightly convex, has some 

 long setae at the upper part, and two or three spinules below these ; the front margin is 

 crenulate, with setules in the notches ; the lower margin projects for some distance in 

 front of the second joint, but is much narrower than the upper margin ; the second joint 

 has a group of slender spines at the hinder apex ; the third is more squared, and with 

 fewer spines than in the first gnathopods ; the wrist is short, triangular, distally cup-like, 

 as broad as long, narrower than the hand, with a few spines at and near the front apex, 

 many round the apex of the hind margin, some on the lower margin ; the hand is very 

 large, widening from the base, considerably longer than its greatest breadth, which is at 



