26 THE VOYAGE OF H.M.S. CHALLENGEK. 



Genus Paralamj^rops, n. geii. 



Generic Characters. — Anterior division of body well defined from posterior. Cara- 

 pace large and sculptured with denticulated crests, dorsal surface vaulted, sides somewhat 

 expanded; pseudorostral projection very slight, subrostral notches obsolete. Ocular lobe 

 very small, eye wanting. Exposed part of trunk composed of five well-defined segments 

 with laterally projecting epimera. Tail very slender. Antennulte unusually large, witli 

 both flao-ella elonoate and multiarticulate. Antennae in female five-articulate, with two 

 strong ciliated setse on the middle j oint. First pair of maxillas without any trace of palp. 

 Second pair of gnathopoda very slender, basal joint not expanded at the end. The two 

 anterior pairs of legs in female with well-developed natatory exopodites, third and fourth 

 pairs with a small biarticulate appendage at the base. Three pairs of pleopoda present 

 in male. Telson narrow, with the edges spinulose. Uropoda slender, inner branch 

 longer than outer. 



Remarhs. — This new genus is chiefly distinguished by the large vaulted carapace, 

 sculptured with serrate crests, the total want of the eye, the strong development of the 

 antennulaj, and the absence of the usual palp on the first pair of maxillse, in which 

 latter respect it diff"ers from all hitherto known Cumacea. In the other anatomical 

 details, it would seem to agree most closely with the genus Ilemilamprops, though in 

 some particulars also exhibiting a certain affinity to the genus Platyaspis. Only a single 

 species of this genus is represented in the collection. 



5. Paralamprops serrato-costata, n. sp. (PL II. figs. 6-13 ; PL III.). 



Specific Characters. — Form of body very slender. Carapace much larger than 

 exposed part of trunk, sculptured by seven longitudinal serrate keels, one median 

 running along the anterior half, two subdorsal on each side, occupying the posterior, 

 somewhat gibl)ous part of the dorsal surface, and two lateral encircling the carapace at 

 the sides and meeting in front. Pseudorostral projection short and somewhat upturned. 

 The three anterior exposed segments of the trunk somewhat gibbous in the dorsal part 

 and armed with small denticles, epimera produced anteriorly as an acute angle. Tail 

 extremely slender and much longer than anterior division of body. Antennulse with 

 the peduncle densely setose ; flagella almost as long as peduncle, inner triarticulate, 

 outer six-articulate. Penultimate joint of antennas in female with outer edge denticu- 

 late. First pair of legs about as long as anterior division of body, the three outer joints 

 very slender, penultimate the longest; second pair nearly as long as first, antepenulti- 

 mate joint strongly s|)inose at inner edge. Telson shorter than scape of uropoda, slightly 

 dilated at base, outer part sublinear, witli about nine pairs of lateral denticles, the last 

 one much larger than the rest, apex with three strong spines of equal size. Uropoda 



