1196 THE VOYAGE OF H.M.S. CHALLENGER. 



with a row of eight setules of different lengths set close together near the base of the 

 sharp curved nail. 



Second Gnathopocls. — The side-plates broader than deep. The branchial vesicles more 

 or less oval, not very large. The marsupial plates of great size, much longer and very- 

 much broader than the first joint of the limb, narrowing distally, surrounded by setae 

 not so long as the breadth of the plate. The first joint larger than in the first gnathopods, 

 but not so long as the hand, widening distally, with a few small spines on each margin ; 

 the second joint as in the first pair ; the third joint a little longer than the second, with 

 spines at two or three points of the hind margin and a group at its apex including two 

 short spines, the distal margin straight ; the wrist very small, scarcely as long as the third 

 joint, which overlaps it, broader than long, with a long spine on the narrow hinder apex ; 

 the hand large, abruptly wider than the wrist, distally narrowing, with spines at four 

 points of the convex front margin, the hind margin very short, carrying two slender 

 spines and forming an apical tooth beyond this. The very oblique, slightly convex, 

 deeply toothed or serrate palmar margin completes the distance required to match the 

 long front margin ; the serrations are occupied by a series of seven or eight strong 

 palmar spines, other slender spines projecting from the surface ; the finger is broad, of a 

 length to match the long palm, the outer margin greatly curved, and having five or six 

 submarginal setules ; the inner margin is nearly straight till the narrow, acute, and 

 inward curving nail is reached ; at the base of this there are three or four setules close 

 together, others being dispersed along the margin, and some extremely small triangular 

 spine-teeth at intervals. 



The Per&opods were unfortunately all missing. The second pair of marsupial plates 

 were similar to the first, but more regularly oval. None of the branchial vesicles were 

 very large. 



Pleopods. — The coupling spines two in number, each having two pairs of retroverted 

 hooks ; there were no discernibly cleft spines ; the joints were seven in number in each 

 ramus, the terminal joint being unusually stout. 



Uropods. — The first pair reaching back much beyond the second, the peduncles as long 

 as the outer, shorter than the inner ramus, with four spines on the outer margin, and a 

 large spine on the lower apex ; the outer ramus with three or four marginal spines, and 

 an apical group of four, of which one is very long ; the inner ramus with seven spines 

 along its slightly pectinate inner margin, three or four on the outer, and the apical 

 group ; the peduncles of the second pair very short, as long as the outer ramus, which 

 has one submarginal spine and the apical group of four, including as in the other cases 

 one very long one ; the inner ramus is a little longer, with two spines on the outer margin, 

 three on the inner, and the apical group ; each of the third uropods is represented by a 

 small inward-bent oval plate, shorter than the telson and not nearly reaching the end 

 of it ; these plates are covered by the telson except for a small strip of the outer margin ; 



