A REVIEW OF THE MYSIDACEA 



207 



(4) The eyes are large and prominent (fig. 80), pigment black, one 

 and a half times as long as broad, the cornea occupying more than 

 half the eye in dorsal view. 



(5) The antennal scale (fig. 81, a) is very long and narrow, 12 to 

 15 times as long as broad. 



(6) The endopods of the third to the eighth thoracic limbs (figs. 81, 

 b ; 82, a, b) have the sixth joint divided into 5 to 7 sub joints, nail well 

 developed. 



(7) The telson (fig. 81, c) is linguiform in shape, 2^/2 times as long 

 as broad at the base, apex broadly rounded and armed with a row of 

 20 to 30 densely set sharp spines between the somewhat larger spines 

 at each angle. The lateral margins are armed throughout their entire 

 length with about 42 spines, rather widely spaced proximally, more 

 crowded distally and with smaller spines between the larger ones. 



(8) The fourth pleopod of the male (fig. 82, c) has the proximal 

 joint of the exopod 2y 2 times as long as the distal joint, and the 

 terminal setae are as long as the distal joint. 



I overlooked the grooves and ridges on the thoracic and abdominal 

 somites in my original description of the species. The specimens from 

 California agree closely with those from British Columbia. This 

 species is distinguished from all others known to me by the supra- 

 ocular spines on the carapace. Otherwise it is perhaps most nearly 

 allied to A. macropsis and to A. pseicdomacropsis, differing in the 

 more normal form of the eye and the details of the telson and fourth 

 pleopod of the male. 



Figure 83. — Acanthomysis sculpta (Tattersall) : a, Last three somites of abdomen, dorsal 

 aspect, X 27}4; b, last three somites of abdomen, lateral aspect, X 27%. 



