1032 THE VOYAGE OF H.M.S. CHALLENGER. 



Second Gnathopods. — Side-plates a little longer than the preceding pair, which they 

 resemble, except that they are not outdrawn in front. Branchial vesicles as long as the 

 first joint, nearly twice as long as broad. First and second joints of the limb as in the 

 preceding pair, but larger ; third joint drawn out to a pointed apex behind as well as in 

 front, with spines at two points of the hind margin ; the wrist only equal in length to 

 the preceding joint, broader than long, cup-shaped, with five groups of spines on the 

 short hind margin, and a couple of short spines at the apex of the front margin ; the hand 

 of great size, longer than the first and second joints united, much broader than the wrist, 

 nearly twice as long as broad, with a few spines along the long front margin, seven or 

 eight groups of setae along the shorter hind margin ; the palm oblique, of very irregular 

 outline ; from the two edges between which the hinge of the finger is inserted arises a 

 large prominence with seven spines, three pairs and an odd one, above its sinuous 

 margin, this prominence being followed by four emarginations, bounded each by a 

 spine, the outermost a very small one, on either side of which there project from 

 the inner surface two processes evidently intended to receive the point of the strong 

 curved finger, as in Cheirocratus sundevallii ; the dorsal cilium is very small, at 

 some little distance from the base of the finger, the inner margin of which shows some 

 small hairs. 



First Pereeopods. — Side-plates similar to those of the preceding segment; branchial 

 vesicles more inflated at the centre. First joint of the limb longer than in the preceding 

 pair, with the front margin rather more sinuous, some very long setae at the upper part 

 of the hind margin ; third joint longer than either the fourth or the fifth, not decurrent, 

 with spines at three points of the front margin, setiform spines or spinules at four points 

 of the hind margin ; the fourth joint equal in length to the fifth, with spines at four 

 points of the hind margin, spinules at two points of the first ; the fifth joint with 

 spines at six points of the hind margin, spinules or small setae at two points of the 

 front ; the finger short and broad, not much more than half the length of the fifth joint, 

 the inner margin forming an angle in front of the little curved nail, two cilia being 

 inserted at this point ; the dorsal cilium small, close to the hinge ; there is another cilium 

 on the dorsal line near the base of the nail. 



Second Pereeopods.- — The side-plates deeply but not widely excavate. The branchial 

 vesicles at the centre as broad as two-thirds of their length. The limb nearly as in the 

 preceding pair. 



Third Pereeopods. — Side-plates not very broad. Branchial vesicles widest distally. 

 First joint of the limb much longer than broad, broader above than below, with spines at 

 eight points of the front margin, the hind margin nearly straight, serrate, forming an 

 angle with the serrate hind part of the lower margin ; the second joint with a group of 

 spines at the apex of the front margin ; third joint with spines at four points of the 

 straight front, and four of the convex hind, margin ; the rest of the limb missing. 



