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



Second Maxillse. — The inner plate a little shorter and considerably narrower than 

 the outer, the spines numerous and strong round the apical margin, descending the inner 

 margin a little way, where the series ends with some densely plumose setse, the largest 

 lowest, the outer plate also with numerous and strong spines round the apical margin, 

 extending a little way down the front and hinder margins. 



MaxilUpeds. — Inner plates rather short and broad, reaching beyond the short first 

 joint of the palp, with five plumose setae along the inner margin, and three stout spine- 

 teeth on the slightly convex distal border, which is fringed with about a dozen sub- 

 marginal curved plumose spines ; outer plates long and rather narrow, reaching about to 

 the end of the narrow second joint of the palp, inner and apical margins fringed with 

 spine-teeth, passing gradually into long curved spines ; in the specimen examined there 

 were ten of the former on the inner, four of the latter on the apical, margin ; second 

 joint of the palp more than twice the length of the first, with many groups of slender 

 spines about the inner margin ; third joint much longer than the first, a little shorter 

 than the second, with many groups of spines about the inner margin, and one group 

 at the centre of the hind margin, which is not as usual evenly convex ; there are also 

 many spines about the apex, which is produced on the outer side ; the finger small and 

 weak, with a spine-like nail, a dorsal cilium not far from the base of the nail, and on the 

 inner margin several setules near and at the base of the nail, those at its base being the 

 longest. 



First Gnathopods. — The side-plates narrower below than above, the front margin bent a 

 little forwards, the corner rounded and crenulate, with spinules in the interstices, the lower 

 part of the hind margin also carrying spines. The first joint extending much beyond the 

 side-plate, expanding distally, the front margin almost straight, with numerous setiform 

 spines, the hind margin more convex, armed with setas and spinules, and on the outer 

 surface carrying six or seven groups of curved spines, and an apical group of about twelve 

 accompanied by long setiform spines ; the short second joint has three groups at the hind 

 margin, followed by an apical group or row of some twenty-four graduated sjnnes, together 

 with some long and slender ones ; the third joint has scarcely any free front margin, 

 some eight groups of spines on the hinder margin, those towards the apex being long and 

 pectinate ; the wrist is long, triangular, with five groups of sjiines on the front and four 

 on the hind margin, the latter having near them rows on the inner surface ; the hand 

 is equal in length to the wrist, with an oblique palm, bordered with many spinules, 

 and defined by several stout palmar spines among which the finger closes ; besides these 

 there are three other groups of spines on the hind margin, with attendant groups on both 

 surfaces, but the most conspicuous ornamentation of the hand is on the inner surface 

 (that shown in the Plate) along the front margin ; here there are seven groups or rows 

 of spines, the number in a row gradually increasing from three near the base to twenty- 

 seven near the finger ; distally the long spines of the hand and wrist are very finely 



