REPORT ON TIIE AMPHIPODA. 043 



plates, its length equal to that of the wrist and hand combined, carrying some 

 long, distally serrate spines or spiniform setae near the front margin ; second joint 

 very short, third longer than broad, carrying on most of the hind margin and along the 

 squared distal margin many long spines, the wrist much longer than the hand, expanding 

 behind and then again slightly contracting, the hinder part armed with many long 

 spines ; the hand longer than broad, narrow at the base, but presently expanding, beset 

 on both margins and surfaces with numerous groups of spines of various lengths, and, 

 like those on the preceding joints, finely pectinate ; the palm border is finely pectinate, 

 a Uttle convex, with some defining spines ; the finger reaching a little beyond the palm, 

 the inner margin produced into a small tooth at the base of the nail, with a cilium ; the 

 dorsal cilium small, near the base. 



Second Gnathopods. — Side-plates deeper than those of the preceding segment, front 

 margin sinuous, its apex pointed forwards. Branchial vesicles large, simple, much 

 longer and broader than the side-plates. Marsupial plates narrower, but longer than the 

 branchial vesicles, with many long setas along one margin and the apex, fewer and shorter 

 on the other margin. The joints of the limb similar to those of the first gnathopods, but 

 with the first, third, fourth, and fifth joints longer. 



First Perseopods. — Side-plates shallow, produced downwards in front into a long 

 tooth directed a little forwards. Branchial vesicles and marsupial plates as in the 

 preceding pair. First joint of the limb broader, but not longer, than the third joint, 

 armed with spines on both margins ; the second joint short, with a group of spines at the 

 apex ; the third joint longer than the next two united, a little curved, with spines on 

 both margins, those on the hinder margin, as in the first joint, the longer ; fourth joint 

 shorter than the fifth, with spines about the distal end ; fifth joint with spines at two 

 points on the front margin and a group of setse at its apex, at the back expanding a 

 little before the end, and forming a sharp tooth tipped with two spines, against which 

 the finger impinges ; between this tooth and the narrow distal end is a large, angular 

 cavity ; there are spines along the surface, and a group close to the hinge of the finger, 

 one being incurved ; the finger itself is much curved, making with the tooth of the hand 

 a powerful grasper ; it has a small dorsal cilium near the base, and a very small cilium on 

 the inner margin near the root of the nail. 



Second Perseopods. — Side-plates a little broader than in the preceding pair, otherwise 

 scarcely differing ; the limb and its appendages also in close agreement with those of the 

 first perseopods. 



Third Perseopods. — Side-plates as broad as the preceding and as deep as their hind 

 margin, the front lobe the deeper and a little pointed. The branchial vesicles like those 

 of the preceding pairs. The marsupial plates short and narrow, with only ten long setse 

 set round the lower part. The first joint longer than the third, with a small expansion 

 confined to the upper part just below the side-plate, spined along both margins ; the 



