166 



THE VOYAGE OF H.M.S. CHALLENGER. 



second foot, 15 postabdomiual laminte. PI. XLI. figs. 11, 12. 11 Carapace of male seen 

 from left side, 12 copulative organ and postabdomen of male.] 



2. Hcdocyioris brevirostris, Dana (PI. XXXIX. figs. 1-11). 



Haloajpris brevirostris, Dana, Crustacea of United States' Exploring Expedition, p. 1303, 

 pi. xci. tig. 9, a-c. 



Carapace, in general shape, very similar to the preceding species, but much shorter, 

 more tumid, and having a much more convex ventral surface, with a less prominent 

 rostrum. Shell of the female (PI. XXXIX. figs. 1-3) seen from the side, highest in the 

 middle, the height equal to nearly three-fourths of the length; rostrum short, broad 

 obtusely rounded and often fringed with four or five short, broad teeth, notch wide and 

 shallow ; ventral margin boldly and evenly convex, forming one continuous curve from 

 the notch to the postero-dorsal angle, both ventral angles well rounded ; dorsal margin 

 nearly straight, but sinua,ted both in front of and behind the middle, and forming an 

 obtuse angle at its junction with the posterior extremity ; seen from above the outline 

 is broadly ovate, greatest width equal to two-thirds of the length, and situated in the 

 middle, extremities subacuminate ; seen from the front, broadly lanceolate, widest above 

 the middle, the width being a little less than the height ; dorsal margin broad, with well 

 rounded angles, compressed below the middle, and subacuminate at the ventral edge. 

 The shell of the male (figs. 4, 5) is smaller, less convex ventrally, when seen from above 

 is much less tumid, and has the greatest width situated behind the middle. The shell in 

 both sexes is perfectly smooth, without any, or only a very faint trace of striation, 

 and is usually much firmer in texture than in the preceding or following species. The 

 anterior antenna (fig. 6) bears five obtusely-pointed and untapering setae, one of which 

 is much longer than the rest, and annulose ; the secondary branch of the posterior 

 antenna in the female (fig. 7) bears five blunt and rather rigid setiform appendages, two 

 of which are longer than the rest ; in the male (fig. 8) there is a terminal hook and 

 a fascicle of setiform filaments, in length similar to those of the female, but the longest 

 is dilated at the apex, and filled with a granular stroma. The other limbs almost exactly 

 as i\i Halocypris atlantica. Length, l-16th of an inch (1-55 mm.). 



Halocypris brevirostris was noticed in the following tow-net gatherings : — 



. _ . Station 159 



Lat. 47° 25' S., long. 130° 12' E., 



Abi to Cape York (Pacific). 



Lat. 35° 11' K, long. 139° 28' E., 



232 

 241 

 287 

 302 

 303 

 330 

 341 



St Vincent, Cape Verde. 



