AMPHIPODA. 13 



Head shorter than the first segment ; ocular lobe broadly triangidar, 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 -join ted, 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, produced 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, 14j fm. ; length 10 mm. 



0. FRANKLINI. 

 O.franUini, A. 0. Walker. 



W.Q., 15 June, 1902 ; D net, nine, various sizes, length of largest 6-5 mm. 



0. CHELIPES. (PI. 4, fig. 7.) 



0. chelipes, A. 0. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 4.56. 



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- 



