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



joint of the palp is short and broad, with spines on the inner margin and outer apex, 

 the second joint is a little longer, similarly armed ; the third joint is as long as the 

 second, with apical spines, not produced at the outer apex ; the finger is as long as the 

 third joint, with a short sharp nail, and the inner margin ciliated. 



The triturating organ of tlie stomach has half of its oval fj-iuged with seventeen 

 unequal spines, each of which has two rows of spinules. 



First Gnathopods. — Side-plates broader below than above, the front lower corner 

 produced, but not reaching the antennjB, the flat lower margin forming more of an 

 angle with the front margin than in the preceding species, the serrations at the lower 

 part of the front margin more marked. The first joint much shorter than the wrist, the 

 margins smooth, the front nearly straight, the hind gently convex ; the second and 

 third joints as in Leucothoe miersi, the third with two setge at the apex ; the process of 

 the wrist prolonged quite round to the hinge of the finger, thin on both margins, which 

 have a few hairs at intervals ; the hand with four to six spines on the distal half of the 

 finely serrate inner margin ; the finger short, about one third tlie length of the hand, 

 not reaching the two uppermost spines. 



Second Gnathopods. — These do not differ very strikingly from those of Leucothoe 

 miersi. The straight hind margin of the side-plate is a little serrate. The hind margin 

 of the second joint has some groups of setules ; the distal margin of the wrist is cut 

 into five distinct denticles, and one of its inner margins is without any serration, the 

 hand has two or three rows of spinules not very closely set on each surface near the 

 palm border, but is without the transverse row of seta3 on the inner surfoce, although 

 there are some groups towards the hinge of the finger ; the apex of the front margin is 

 not sharply pointed. 



First Pe?'«opocZ5.— Side-plates nearly square, a little deeper than Ijroad. The 

 branchial vesicles narrowly oval, not so long as the first joint, the marsupial plates 

 about as long as the branchial vesicles, narrower, fringed with long setse. The first 

 joint widening a little distally, with the front margin concave, the hinder convex, both 

 fringed with spinules ; the relative proportions of the third, fourth, and fifth joints as in 

 Leucothoe miersi, the third joint with a spine at the upper, another at the lower part of 

 the hind margin, and a third at the apex, the fourth joint with three, and the fifth with 

 four, little spines on the hind margin ; the finger more than half the length of the fifth joint. 



Second Perieopods. — The side-plates four-sided, the hind margin shorter than the 

 front ; the lower margin has two little notches indicating the portion perhaps which 

 technically should be reckoned as hind margin. The branchial vesicles rather larger 

 than the preceding pair, the marsupial plates and the joints of the limb not showing any 

 material difference. 



Third Perseopods. — Side-plates with the front lobe wider and rather deeper than 

 the hinder one. The branchial vesicles rather longer than the first joint, but not so broad. 



