REPORT ON THE AMPHIPODA. 7(ll 



this and the two preceding joints ; the hand considerably longer than the wrist, tapering 

 distally so as to have no palm, almost the whole of the hinder margin pectinate, with 

 setae at intervals, and a few pectinate spines on the side ; finger short, curved, with a 

 dorsal cilium near the hinge, one on the inner margin, and one or two at the nail. 



Second Gnathojwds. — Side-plates small and narrow, longer than those of the first 

 segment. First joint narrow, a little bent back distally, about equal in length to the 

 wrist and hand united ; second joint longer than the third, shorter than the hand ; 

 third joint with a solitary cilia-like spine near the pointed apex ; wrist longer than the 

 hand, with the hind margin straight, furred, and carrying some pectinate spines, chiefly 

 at the lower end, the front margin nearly parallel with it, smooth ; the hand long, 

 dilating gradually towards the palm, wider than the wrist, furred on the hinder margin, 

 with groups of pectinate spines on the lower part of it ; the palm oblique, slightly 

 sinuous, with a row of three short stout spines near the angle on one side and one or 

 two more on the other, cilia along its course, and some minute pectination ; the small, 

 curved finger, hinged very near the front margin amid over-arching pectinate spines, 

 does not nearly reach the end of the palm ; its dorsal cilium is very long. 



First Peraiopods. — Side-plates narrow, oblong, with a distally narrowed termina- 

 tion, a little longer than those of the preceding segment. First joint shorter than 

 the side-plate, its front margin straight, the hind convex, with very short setae at 

 intervals ; third joint broader than fourth, ec[ual in length, scarcely decurrent ; fourth 

 joint shorter than the fifth, with three spines along the hind margin ; fifth joint with 

 the hind margin straight, front convex, armed only with some minute cilia ; finger 

 straight to the sharp, slightl}^ curved tip ; dorsal cilium close to the hinge, very small. 



Second Peraiopods. — Side-jilates greatly developed, the front margin straight, ex- 

 tending forward below the head, the side-plates of the three previous segments forming 

 a triangle, the apex of which is shut in below by the lower angle of the head on one side 

 and the fourth side-plate on the other ; its lower margin is curved, and the curve is 

 continued so as to form a large rounded lobe behind, where the excavation causes the 

 upper part of the side-plate to be not more than one-third the width of the lower part ; 

 there are minute cilia set round the edge and on some other parts ; the joints of the limb 

 are similar to those of the preceding pair, but the fourth and fifth joints are here a little 

 shorter. 



Third Perseopods. — The side-plates with the hinder lobe produced much below the 

 front one ; the first joint with the front margin nearly straight and armed with a few 

 small spines, the hinder margin sinuous, running out into a smooth-edged, rounded, 

 backward-directed lobe, so as to be much broader below than above ; second joint over- 

 lapped behind by the lobe just mentioned ; the third joint very much broader than the 

 fourth, decurrent, spined on both borders ; fourth joint shorter than the hand, spincd on 

 the front margin, largely overlapped behind b}^ the decurrent part of the third joint ; 



