1090 THE VOYAGE OF H.M.S. CHALLENGER. 



the slightly blunted angle which it makes with the finely pectinate, nearly straight 

 palm ; the finger is stout and short, with a rather long dorsal cilium near the base ; its 

 inner margin cut into teeth, the tip of the nail projecting just beyond the palm ; the 

 surface of the hand has several slender spines besides those on the margins. 



First Perzeopods. — Side-plates smaller, branchial vesicles larger, than in the preceding- 

 segment. The first joint of the limb nearly free from the side-plate, well packed with 

 gland-cells, the front margin straight, the hinder slightly convex, both armed with small 

 spinules, the hinder having also a seta or setiform spine high up ; the second joint short, 

 with apical spinules ; the third longer than either the fourth or fifth, dilated a little 

 distally, with slight spines at either apex, and a spinule on each margin ; the fourth joint 

 shorter than the fifth, with spines at two points on the hind margin and at the apex in 

 front ; the fifth joint with slender spines at thiee points on the upper half of the straight 

 hind margin and one of the convex front, some spinules on either side of the narrowed 

 rounded apex ; the finger narrow, more than half the length of the fifth joint, with a 

 dorsal cilium near the base, and an opening at the tip. 



Second Per&opods not materially differing from the first. 



Third Perseopods. — The side-plates broad, the front lobe deeper than the hinder, as 

 deep as the preceding side-plates. The branchial vesicles narrowly oval, much shorter 

 and narrower than the first joint of the limb. The first joint not greatly expanded, more 

 than twice as long as broad, the sides slightly convex, with some slight spines at the 

 front apex and spinules elsewhere ; the short second joint with similar spines at the front 

 apex ; the third joint broader and longer than the fourth, not longer than the fifth, with 

 some small spines at each apex, and one or two spinules on the front margin ; the fourth 

 joint with strong spines at two points near the hind margin and two at its apex with a 

 slender spine ; the fifth joint with spines at four points of the front margin, these being 

 stronger than those of the upper joints, and with a group of longer spines at the apex 

 of the convex hind margin ; the finger upward bent, less than half the length of the 

 fifth joint. 



Fourth Perieopods much longer than the third. The side-plates and branchial 

 vesicles smaller than in the preceding pair. The first joint with several plumose setae 

 or setiform spines on the hind margin, otherwise like the first joint of the preceding- 

 limb, but longer and wider; the third joint elongate, much longer than the fourth, 

 subequal in length to the fifth, with slender spines at four points of the hind margin, 

 slenderer spines at two points of the front margin, and spinules elsewhere ; the fourth 

 joint similarly armed in front, but behind having a strong spine at two points near the 

 hind margin, and two strong spines and some slender ones at its apex ; the fifth joint 

 with spines at five points in front and some spinules behind ; the finger acute, upward 

 curved, not half the length of the fifth joint, with a long dorsal cilium at the base. 



Fifth Perseopods much longer than the preceding pair, and twice as long as the third 



