EEPOET ON THE AMPHIPODA. 761 



nearly straight. Branchial vesicles pear-shaped, much broader below than above, not as 

 long as the first joint. Marsupial plates broad and long. First joint reaching a little 

 beyond the side-plate, with setse and setules along the margins ; third joint longer than 

 the fourth, shorter than the fifth, a little decurrent in front ; there are a few setules and 

 spinules on the margins and apices of these joints ; the finger long, thin, pointed and 

 curved, more than half the length of the fifth joint. 



Second Peraiopods. — Side-plates rather deeper than broad. Branchial vesicles pear- 

 shaped, bent, as long as the first joint. Marsupial plates broad, not as long as the side- 

 plates. Neither first nor second joint reaching the end of the side-plate ; the third joint 

 longer than either the fourth or the fifth ; the fourth shorter than the fifth, each with 

 four groups of spines on the hind margin ; the finger broad, shorter than in the preceding 

 pair, much curved at the tip, with the inner margin a little serrate. 



Third Perieojyods. — Side-plates deeper than broad. Branchial vesicles short, widest 

 just below the neck. First joint of the limb not expanded above, but forming a rounded 

 lobe below and behind which partially overlaps the second joint, with nine spinules on the 

 hind margin, and five or six on the lower half of the front ; second joint with spines at 

 two points in front ; third joint much broader as well as longer than the fourth or fifth, 

 with spines at six points in front, and spinules at as many on the convex decurrent hind 

 margin ; the fourth joint shorter than the fifth, each with spines at four points of the 

 front margin ; the finger much more than half the length of the fifth joint, curved at the 

 tip, the inner margin smooth. 



Fourth Perxopods. — Side-plates similar to the preceding pan-, but smaller. First 

 joint evenly expanded or a little wider above than below, with a few spines along the 

 front margin, the hinder almost completely smooth, the rounded lower margin partially 

 overlapping the second joint behind ; the third and fifth joints rather larger than in the 

 third perajopods. 



Fifth Perasopods. — The side-plates smaller than the preceding pair. The first joint 

 wider than in the preceding pair, and behind quite overlapping the second joint ; the third 

 joint shorter in front than in the fourth perseopods ; the finger with serrate inner margin. 



Pleopods. — Coupling-spines seemingly minute ; a single cleft spine on the inner 

 ramus ; joints of the rami seven to nine in number. 



Uropods. — Peduncles of the first pair rather longer than the rami, with spines on the 

 pectinate upper edges ; inner ramus a little shorter than the outer, with two marginal 

 sprues, the outer with three, both with the upper edges pectinate ; peduncles of the 

 second pair subequal in length to the inner ramus ; the outer ramus much shorter than 

 the inner, with one marginal spine, the inner with two, both with i)ectinate upper edges ; 

 peduncles of the third pair a little shorter than the ramus, with four spines along the 

 margin ; the basal portion of the ramus shorter than the naU, carrying two spines on the 

 upper margin, the upper edge of the nail pectinate. 



(ZOOL. CHALL. EXP. PART LXVII.^ — 1887.) Xxx 96 



