1368 THE VOYAGE OF H.M.S. CHALLENGER. 



First Perteopods. — The first joint has three small teeth on the lower part of the hind 



margin. 



Second Perseopods. — The first joint has seven teeth along the hind margin, this joint 

 beino- nearly as long as the three following together ; the third joint is nearly as long as 

 the fifth, while the fourth is noticeably longer than either. 



Third Perseopods much longer than the second. Branchial vesicles little more than 

 a fifth the length of the first joint. The first joint with twelve little unequal teeth along 

 the front margin, and six or seven along the hind margin ; the second joint with four or 

 five very small teeth on the front, the third joint with six or seven ; the fourth joint 

 with the largest tooth the eleventh, below which the palm has three, the lowest blunt ; 

 the fifth joint though larger than in the male specimen, is little more than a third the 

 length of the fourth joint, the large tooth of which touches its upturned inner margin a 

 little below the centre. 



Fourth Peneopods. — Branchial vesicles longer than the preceding pair, elongate, but 

 less than half the length of the first joint. First joint elongate, much shorter than 

 in the third peraaopods, a little longer than the three following joints together, 

 proximal part narrow, distal half widened, with the gland-cells conspicuous, the front 

 margin forming a small apical tooth ; the second joint considerably longer than broad, 

 with a small apical tooth in front ; the third joint a little more than twice as long as the 

 second ; the fourth about twice as long as the third ; the fifth scarcely so long as the 

 third. 



Fifth Perseopods shorter than the fourth. First joint longer than in the preceding 

 pair and a little more slender, much longer than all the remaining joints together, the 

 second a little longer than broad, the third not more than twice as long as the second ; 

 the fourth more than twice as long as the second, less than twice as long as the 

 fifth. 



Pleopods. — Peduncles elongate, especially in the first pair. 



Uropods more elongate than in the male specimen, except the second pair, which are 

 reduced to a minute oval joint not long enough to reach the base of the telson ; at the 

 apex there is a hair or very small setule. 



Telson very small, broader than deep, almost too flat-ended to be called semicircular, 

 not reaching clear of the ventral opening. 



Length. — The largest of the female specimens measured three-tenths of an inch 

 from the front of the head to the end of the perseon, and four-tenths from the latter 

 point to the extremity of the uropods, in all when fully extended seven-tenths of an 

 inch. 



Locality. — Station 230, April 5, 1875; North Pacific, south of Japan; lat. 26° 29' 

 N., long. 137° 57' E.; surface; surface temperature, 68°'5. Seven specimens ; one male, 

 six females. 



