1150 THE VOYAGE OF H.M.S. CHALLENGER. 



than broad, with spines near the apex in front ; the third joint longer than the fourth, 

 not quite so long as the fifth, the margins almost parallel, with slender spines at the 

 apices and a spinule or two higher up ; the fourth joint similar, a little narrower, and 

 with stout spines as well as the slender at the apex behind ; the fifth joint also with the 

 marcins nearly parallel, but the hinder a little convex, having slender spines at the apex, 

 the front margin almost straight, with four groups of short strong spines, besides some 

 that are setiform ; the lower part furry ; the finger strong and curved, more than half 

 the length of the fifth joint, with a feathered dorsal cilium near the hinge, and another 

 near the base of the nail ; the concave inner margin strongly furred, and produced into 

 a short thick tooth at the base of the short nail, the tooth having at its base a feathered 

 spiniform seta which is prolonged over the inner margin of the nail. 



Fourth Peneopods. — The side-plates smaller than the preceding pair, the front 

 margin fringed with feathered setae, the convex lower margin of the front lobe smooth, 

 the straight lower margin of the hind lobe having some strong spines. The branchial 

 vesicles not so long as the first joint, broadest a little below the neck. The limb similar 

 to that of the third peraeopods, but all the joints longer, the third rather longer instead, 

 of rather shorter than the fifth, the spines more numerous. 



Fifth Perseopods like the fourth, but all the joints longer. 



Pleopods. — The coupling spines have a stout base, a slender shaft, somewhat bent, 

 the apex forming a strongly bent hook between a pair of lateral hooks, which are also 

 strong ; the cleft spines appear to be a series of five in each pair ; the joints of the rami 

 number from ten to twelve, the outer ramus being considerably the shorter. 



Uroj)ods. — The peduncles of the first pair considerably longer than the rami, with 

 marginal spines, and a spine-process with a broad base on the lower apex ; the rami 

 equal in length, reaching beyond the other two pairs, the outer with four short spines on 

 the outer margin, three not so stout on the inner, and a group at the rounded apex, 

 consisting of two subapical and a large apical between two much smaller spines ; the 

 other ramus has four on the outer, five on the inner, margin, and the apical group ; the 

 peduncles of the second pair are longer than the rami, and have a few spines ; the outer 

 ramus nearly equal to the inner, with three stout spines on the outer margin, one more 

 slender on the inner, and the apex as in the first pair ; the inner ramus has six spines on 

 the inner, four on the outer, margin, and the apical group ; the peduncles of the third 

 pair are short and broad, just reaching beyond the telson, but not so far as the peduncles 

 of the second pair, with a couple of feathered setae or setules near the outer apex ; the 

 rami are diminutive, equal, narrowly oval, not reaching beyond the peduncles of the 

 second pair, the inner carrying a slender feathered spine at the apex, another just above 

 it on the outer side, and a third higher up on the inner side ; the outer has a much longer 

 apical spine, which is distally setiform, and a shorter one just above it on the outer side. 

 Telson broader than long, distally arched in outline, with a blunt central point ; 



