948 THE VOYAGE OF H.M.S. CHALLENGER. 



margins being serrate or indented, the notches armed with spinules ; the hind margin 

 is nearly straight, a little bent in near the centre. The first joint reaches beyond the 

 side-plate, is curved, and distally widened, the front margin concave, the hinder convex; 

 the second and third joints are short ; the wrist is triangular, shorter than the hand, 

 Ion o-er than broad, with long spines at the apex of the hind margin as well as some 

 hi o-her up ; the hand at its base is almost as wide as the wrist, and widens towards the 

 palm, which is very slightly convex, making something more than a right angle with the 

 hind margin, and something less than a right angle with the front ; a row of four 

 palmar spines is planted on the surface near the point where the palm begins ; the 

 finger is gently curved, nowhere very broad, the edges smooth, but with a dorsal cilium 

 near the base, and a decurrent tooth formed by the inner margin near the base of the 

 small acute nail, which seems to reach beyond the palm. 



Second Gnathopods. — The side-plates rather larger than the preceding pair, the 

 front margin more convex, smooth, the lower margin narrow, indented, carrying three 

 or four spinules, the hind margin nearly straight. The limb very similar to the 

 preceding, but with the first joint longer and more curved ; the straight hind margin 

 of the hand has two spines ; the paint-margin is finely pectinate and fringed with 

 spinules ; but probably all these particulars apply also to the hand of the first 

 gnathopods ; the finger fits the palm. 



First Perseopods. — The side-plates rather larger than the preceding j>air, with the 

 lower margin oblique, armed like the others. The branchial vesicles not quite as long or 

 wide as the side-plate. The first joint attached a little above the middle of the side-plate 

 and reaching a little below it, curved, widening a little distally, the hind margin convex, 

 with one or two spinules, the front margin concave, with a spine at the apex. The 

 second joint short, with a little spine on the hinder apex ; the third joint a little longer 

 and broader than the fourth, each with a spine near the middle of the hind margin and 

 two or three at its apex ; the fifth joint rather longer than the third, with sjnnes at three 

 points of the hind margin, and a couple of setules on the front ; the finger three-quarters 

 the length of the fifth joint, straight, except at the nail, with a small dorsal cilium near 

 its base, and another at the base of the nail. 



Second Perseopods.— -The side-plates broader than the preceding pair, with five 

 spinules on the nearly straight, slightly oblique lower margin, and one on the hind 

 margin. The first two joints as in the preceding pair. The rest missing. 



Third Perseopods. — The side-plates with convex front margin, produced below in a 

 little lobe almost to the depth of the preceding plates, the lower margin beyond the lobe 

 nearly straight and parallel with the upper, carrying spinules. the hind margin nearly 

 straight, with one spinule near the rounded lower corner ; these plates are much broader 

 and not much less deep than the preceding pair. The branchial vesicles somewhat 

 pear-shaped. The limb missing. 



