AMPHIPODA. 
13 
Head shorter than the first segment; ocular lobe broadly triangular, produced 
beyond the end of the peduncle of the upper antennse. Eye moderately large, oval, dark. 
Upper antennse : First joint three times as long as the next two united, naked. 
Flagellum 13-14-jointed, the first joint as long as the next three, sparsely setose on 
the upper side. Appendage 5-jointed, the first joint the longest, the third the shortest. 
Lower antennse rather longer than the upper ; peduncle reaching the end of the third joint 
of the flagellum of the upper ; first joint the longest, second the shortest. First 
gnathopods: Side plates narrowed and rounded below ; wrist two-thirds of the length 
of the hand, which is about twice as long as wide, with parallel margins, setose ; palm 
rather oblique, convex, crenulate, defined by a spine. Second gnathopods as in Orchomene 
humilis (Costa) [=0. batei, Sars]. Third perseopods : Side-plates wider than the depth 
in front, with the usual posterior lobe ; first joint about half as large as the side-plate, 
deeper than wide ; hind margin convex, serrate, iiroduced down to the middle of the 
third joint; this is much produced behind and downwards. The fifth perseopods have 
the first joint nearly twice as deep as wide, and longer than the rest of the joints, including 
the dactylus, together, otherwise like the third pair ; the dactyli of all the perseopods 
are very short. 
The first uropods are subequal in extent to the second, exceeding the third; the 
peduncle is one-fourth longer than the subequal rami, all the parts very spinous on the 
upper margins. Second, pair less spinous. Peduncle in the third pair rather longer 
than the outer ramus : inner ramus not nearly reaching the end of the first joint of the 
outer, its inner margin minutely serrate. Telson entire, deeply concave above, the end 
truncate with two setules: it extends beyond the end of the inner rami of the third 
uropods. 
The difference between the telson of this species and that of the female 0. humilis 
is only one of degree, as the truncate margin is slightly concave. 
Orchomenella pin guides. 
Orchomenella pinguides, A. 0. Walker. 
W.Q., March to October,1902 ; ten, 14^ fm. ; length 10 mm. 
O. FRANKLINI. 
0. franklini, A. 0. Walker. 
W.Q., 15 June, 1902 ; D net, nine, various sizes, length of largest G‘5 mm. 
0. CHELIPES. (PI. 4, fig. 7.) 
0. chelipes, A. 0. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 456. 
W.Q., 28 Feb., 1902 ; eight., 10 fm. 
Body moderately compressed; first and second segments subequal to the head and 
each other, remaining mesosome segments rather longer and subequal. First four side- 
tfoy. 
l c f0j(e.(Q.IKtH2>b 
/joy. 3 
