1122 THE VOYAGE OF H.M.S. CHALLENGER. 



are three that are subapical, ten on the inner apical corner, close-set, and two more 

 spaced on the outward sloping part of the distal margin. 



Maxillipeds. — The inner plates reach a little beyond the first joint of the palp ; they 

 have seven plumose setae along the inner margin, three or four on the surface adjacent ; 

 and a spine-tooth just below the apex ; the distal margins slope a little outwards and 

 carry five or six feathered spines, but not more, so far as I could see, than one spine- 

 tooth ; the outer plates reach beyond the second joint of the palp, and have on the 

 crenate and finely pectinate inner margin eight spine-teeth, two more on the distal 

 margin, followed by three setiform spines on the outer curve ; the first joint of the palp 

 is short, with a small spine on the outer margin a little below the rounded apex; the second 

 joint is not twice as long as the first, its inner margin is fringed with not numerous 

 spines ; the third joint is not longer than the first, with some spines along the front 

 margin, and a group of five at the outer apex, of which two are conspicuously pectinate 

 for part of their length ; the finger is almost as long as the third joint, if the ungual 

 spine or nail be included ; there is a minute dorsal cilium near the base, and on the 

 inner margin near the origin of the nail, which is pectinate on the inner side, there are 

 two setules, one shorter, the other longer than the nail. 



First Gnathopods. — Side-plates almost triangular, the rounded front corner being 

 strongly produced forwards towards the base of the lower antennas. The first joint 

 reaching a little distance below the side-plate, with three long setse on the upper part of 

 the convex hind margin, and a few others on the surface ; the front margin tending to 

 concave ; the second joint short ; the third with a very short front margin, the hind 

 margin convex, with a spinule below the middle, and a slender spine near the apex ; the 

 wrist not quite so long as the hand, but as broad, the convex front margin smooth, the 

 hind margin also smooth, furnished with half a dozen slender slightly feathered spines, 

 the surface having three or four more ; the hand widens from the base to the palm ; the 

 long front margin is very slightly convex, with three or four small groups of spines at or 

 near it ; the hind margin is also but slightly convex, at first smooth, but near the palm 

 carrying three little groups of spines followed by a palmar spine, where with a smooth 

 curve it passes into the oblique palm border, which is set with several submarginal slender 

 spines of different sizes ; the finger is short, stout, and curved, with a small dorsal 

 cilium near the base ; the inner margin is at first finely pectinate, then cut into five 

 teeth of gradually increasing size ; there is one small setule near the first of these, and 

 three near the last, which is followed by the sharp curved nail. 



Second Gnathopods smaller than the first. Side-plates narrower but rather deeper 

 than the preceding pair, with a long seta at the hind corner of the convex lower margin. 

 The branchial vesicle much shorter and narrower than the side-plates. The first joint 

 is armed with long setse as in the first pair; it does not reach so far beyond the side-plate, 

 that being deeper ; the third joint with the front margin straight, almost wholly applied 



