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



wrist large, twice as long as the hand, and much broader, the front margin straight and 

 smooth, the hinder convex, fringed almost all round with strongly pectinate spines and 

 setse, with setse also on its surfaces ; the hand with a narrow neck, the convex front 

 margin furred slightly, the hind margin straight ; round the serrate distal half of the 

 hand is set a fringe of spines ; on the apex a little tubercle represents the finger, from 

 the apex of the tubercle projects a nail or short sharp spine, and a cilium about twice the 

 length of the naU. 



Second Gnathopods. — Side-plates large and broad, narrowed a little distally, with 

 cilia round the lower part of front and the lower margin. Branchial vesicles simple, not 

 very large ; marsupial plates small in the specimen examined, with cilia at intervals. 

 First joint long, reaching below the side-plate, a little curved, the concavity facing 

 forwards ; the second and third joints very short and small, the third rather longer than 

 the second, with an angular lappet on the outer side near the base ; the wrist very 

 elongate, all but as long as the first joint, narrowing distally but in no part broad, 

 carrying on either side a series of very long, distant setse, sparsely plumose with long 

 distant cilia ; the hand long and narrow, narrowest at either end, more than half the 

 length of the wrist, which it resembles in armature, but with the upper part of the almost 

 straight hinder margin free from setse ; there are four long setse at the apex, one point of 

 which projects beyond the rest, but there seems to be no representative of a finger ; to 

 the setse in question lines could be traced running the whole length of the hand. The 

 first joint, wrist, and hand are adapted to fold up closely side by side ; to a more limited 

 extent this is the case in the first gnathopods also. 



First Perwopods. — Side-plates deeper and broader than the preceding pair, widest 

 distally. Branchial vesicles and marsupial plates much as in the preceding pair. First 

 joint not reaching to the end of the side-plate, distally in front slightly lobed, behind 

 carrying a row of long plumose setse ; second joint short, hind margin furred, apex with 

 setse ; third joint shorter than fourth, dilated, widest apically, scarcely decurrent, with 

 setse on both margins ; fourth joint dilated, widest proximally, with setse on front, hind, 

 and apical margins ; fifth joint shorter and very much narrower than the fourth, straight, 

 narrowing distally, with spines or setse at two points of each margin, and a group at the 

 apex, at which a cilium marks the place where the finger is not, unless it be represented 

 by a little triangular point near the cilium, within the apical margin. 



Second Perwopods. — Side-plates scarcely deeper than the preceding but much broader, 

 a little broader than deep, with no excavation behind worth calling such. First joint 

 not reaching the end of the side-plates, with a longer row of plumose setse on the hind 

 margin than in the preceding pair ; third joint longer and broader than the fourth, with 

 spines at two points of the hind margin, and at the apex before and behind ; the fourth 

 joint not dilated, a little furred on the front margin, with a spine at the middle of the 

 hind margin, and a group at its apex ; the fifth joint straight, slender, narrowing a little 



