1422 THE VOYAGE OF H.M.S. CHALLENGER. 



or three spinules along the hind margin, and a spine at its apex ; the fifth joint much 

 longer and more slender than the fourth, with a little spine high up on the convex hind 

 margin, and one a little lower down on the pectinate front margin ; the finger slender, 

 curved at the tip. 



Fourth Per&opods rather longer than the third ; the first joint with eight spines 

 along the front margin, which is almost straight like the hind margins ; the second joint 

 as in the preceding pair, the third joint more elongated than in that pair, the fourth 

 joint with one or two additional spines, and the fifth joint more elongate, with four 

 spines on each margin ; the finger about a quarter of the length of the preceding joint. 

 The branchial vesicles to this pair are much broader at the upper part than is the case 

 with the preceding pairs. 



Fifth Peraeopods shorter than the third pair ; the first joint rather longer than in 

 the fourth pair, but the third, fourth, and fifth joints shorter, with the front margin not 

 pectinate as in the other two pairs. 



Pleopods. — The peduncles with some slender marginal spines ; the cleft spine with 

 the arms nearly equal, that with the subapical dilatation slightly the longer, the other 

 conspicuously roughened on the inner side ; the rami slender, with ten joints apiece. 



Uropods. — Peduncles of the first pair a little longer than the inner ramus ; the rami 

 elongate, the outer considerably shorter than the inner, the adjacent margins strongly 

 pectinate, with a slight emargination near the base, in which the teeth are very closely 

 set ; peduncles of the second pair shorter than the inner ramus, which is longer and 

 much broader than the outer; the outer just reaching beyond the peduncle of the third 

 pair ; the adjacent margins of the rami strongly pectinate, the teeth being themselves to 

 some extent pectinate ; the peduncles of the third pair as long as those of the first and 

 broader, considerably longer than the rami, the inner apex produced, acute ; the rami 

 reaching a little beyond those of the first pair, the apices very narrow and acute, the 

 outer ramus narrower and a little shorter than the inner, pectinate only on the inner 

 margin, the inner pectinate on both margins with pectinate teeth, but at the upper part 

 of the inner margin not toothed, only very finely pectinate. 



The Telson scarcely longer than the breadth at the base, scarcely a third of the 

 length of the peduncles of the third uropods, the sides converging with a gentle curve 

 to a narrowly rounded apex, which does not reach the meeting point of the inner 

 margins of the peduncles just mentioned. 



Length, three-tenths of an inch. 



Locality. — Station 240, June 21, 1875; Pacific, between Japan and the Sandwich 

 Islands ; lat. 35° 20' N., long. 153° 39' E.; surface ; surface temperature, 64°-8. Seven 

 specimens ; the specimen described, a male. 



Remarks. — The specific name refers to the ocean in which the species was captured. 



