no. 2065. THE CRUSTACEA EUPHAUSIACE A— HANSEN. 103 



34. TESSARABRACHION OCULATUM H. J. Hansen (1911). 

 Plate 4, figs, la-lm. 



1911. Tessarabrachion oculata H. J. Hansen, Bull, l'lnst. Ocean. Monaco, No. 210, 

 p. 47. 



Occurrence. — It has been taken at three stations in the boreal 

 Pacific : 



Sta. 4793. June 16, 1906. Lat. 54° 48' N.; long. 164° 54' E. 

 Toperkoo Island, not far from Bering Island. 300-0 fathoms. 

 3 specimens (male, female). 



Sta. 4759. May 20, 1906. Lat. 53° 05' N.; long. 138° 31' W. 

 3 specimens. 



Sta. 4806. June 26, 1906. Lat. 42° 13' N.; long. 144° 21' E., 

 off northern Japan. 200-0 fathoms. 9 specimens (male, female). 



Description. — The small frontal plate (fig. It) has the apex sub- 

 acute or a little rounded, and behind this end the plate is concave, 

 which is due to the fact that the front marginal part of the carapace 

 is above and thence downward below the middle of the sides, somewhat 

 expanded, and bent respectively upward and outward as a kind 

 of collar. The lateral margin of the carapace without any denticle. 



The eyes are very large (figs, la-lb), considerably higher than 

 broad, divided by a feeble constriction not much above the middle, 

 and the upper section is nearly as broad as the lower. 



Antennulse in the female (figs. 16 and 1c) with the third pedun- 

 cular joint slightly or scarcely longer but conspicuously more slender 

 than the second; the lower flagellum is about as long as the sum 

 of the two preceding joints, 17-jointed; the upper flagellum is about 

 15-jointed and slightly or considerably shorter. In the male 

 (fig. Id) the two distal peduncular joints are conspicuously thicker 

 than in the female and the third at least as thick as the second; 

 both flagella are somewhat longer than in the female, with about 

 17-18 joints in each flagellum. The antenna! squama reaches in 

 the female the middle of the third antennular joint; it is somewhat 

 narrow (fig. If), with the outer margin concave and terminating in 

 a denticle. 



The two anterior pairs of legs are very elongate, the fourth joint 

 reaching to or beyond the end of the antennular peduncle (fig. la), 

 but this joint is comparatively feebly thickened and subcylindrical. 

 The fifth joint is naked excepting two small spines on its distal por- 

 tion, and it is more than two and a half times as long as the sum of the 

 two distal joints. The sixth joint has about eight spinif orm setse along 

 its prehensile margin and six or seven stiff setas on the other margin. 

 The seventh joint about as long as deep, with two somewhat long, 

 curved spines and a few shorter spines; these spines are distinctly 



