18 EEV. T. R. R. STEBBING ON THE 



beyond which the capped tip of the finger reaches ; the finger carries two or three 

 setules. 



Second gnathopods. Side-plates distally widened, the lower distal angle not having, 

 as in the first pair, a produced point, carrying a group of seven setules. The sack-like 

 branchial vesicle as long as or longer than the first joint. The limb diff'ers from that 

 of the first pair in having the first joint more elongate, with two instead of four groups 

 of setiB on the inner surface ; the long setae on the second and third joints are more 

 numerous; the wrist is narrower and without the special armature of the distal 

 margin ; the hand has less of the hind margin furnished with setae, and the palm a little 

 less oblique ; the finger is decidedly shorter, its tip reaching very little beyond the 

 palmar spine. 



First perceopods. Side-plates widened below, with six or seven spinules on the upw"ard 

 curved hinder part of the lower margin. Branchial vesicle longer than the first joint, 

 nearly uniform in breadth, except at the point of attachment. First joint straight, with 

 setae at the apex of the hind margin, and near that of the front; second joint with a 

 group of setae about the apex of the hind margin ; third joint as long as the fourth and 

 fifth joints together, having groups of setae along the hind margin, and near it a trans- 

 verse group high up on the outer surface, which also carries an oblique series near the 

 apex of the convex front margin ; the fourth joint nearly as broad as the third, with an 

 oblique group of setae approaching the distal end of the front margin, several bent 

 plumose setae and four graduated stout spines along the undulating hind margin, one 

 stout spine and four setae on the distal border, which projects strongly behind tlie fifth 

 joint; the fifth joint a little shorter than the preceding, and scarcely half its width, 

 carrying seven or eight unequal short spines directed towards the finger, the distal part 

 of the hind margin undulating ; the finger straight, except at the tip, with five tubercles 

 along the hind margin, which, with the spines of the fourth and fifth joints, must give 

 it a prehensile character ; the slightly bent tip has a transparent cap. 



Second perwojjods. Side-plates broader than in the preceding pair, with the spinules 

 not grouped at the corner, but spread along the lower margin. Branchial vesicle much 

 dilated below the long neck. Limb scarcely differing from that of first pair, except 

 that the first and third joints are longer, and the first is a little sinuous. 



Third perceopods. Side-plates with the hind lobe deeper than the front, its margin 

 crenulate with spinules in the indents. Branchial vesicles narrowed at the two 

 extremities. The first joint very broad, distally widened, the wing often darkened 

 by the crowd of gland-cells, the upper corners rounded, the lower hinder angle not 

 very acute, sometimes rounded, the front margin rather sinuous, with two or three 

 spinules above, two groups of setae below, and a few spines at the apex, the hind 

 margin crenulate, and having about a dozen setae, the straight lower margin of the 

 wing carrying two or three setules ; the second joint not half the width of the first, but 

 broader than long, with a group of setae and a spine at the apex of the front ; the third 



