Boone, Crustacea, Cruise of "Alva," 1931 55 



terior margin of each spine. The dorsal surface is decidedly ele- 

 vated in the median region, moderately convex and sloping gradu- 

 ally toward either side and toward the front. The entire dorsal 

 surface is covered with coarse, low, convex squam.ae, each of which 

 has the anterior margin rounded and margined by fine short setae. 

 There is approximately a median longitudinal line of these squa- 

 mae which are larger than the others ; there are also a few other 

 large squamae scattered on the median area; towards the front 

 and sides the squamae become much smaller. The orbital margin 

 is circular and beaded with squamae. 



The eyes are set upon short, stocky, calcareous-covered stalks 

 and have large, hemispherical, black cornea. 



The rostral segment is shield-shaped with pointed apex; the 

 dorsal surface covered by small squamae. 



The antennulae are slender, arising side by side beneath the 

 base of the rostral joint ; the first article is much the stoutest and 

 clavate, laterally compressed, distally tapered, with one small 

 spinule on the upper distal margin ; the second and third articles 

 are subequal in length to the first but are successively slenderer ; 

 the flagellum is rudimentary, two-branched, each branch less than 

 the third article in length; the larger branch bears a small tuft 

 of setae. 



The antennae have the basal article wider than long, obliquely 

 truncated, extending from the outer orbital margin to the apex 

 of the rostrum ; the inner lateral margins of the antennal joints 

 surround the rostrum.. The distal margin of each antennal joint 

 is a sharp tooth ; the second antennal joint is greatly expanded, 

 laminate, with the outer lateral margin a little rounded and cut 

 into eight acute procurved teeth, which are in line with those of 

 the lateral border of the carapace and successively increase in size 

 from the proximal to the distal one; across the irregular distal 

 margin of this segment there are two sharp teeth, successively 

 smaller, just inside of the outer distal tooth, there are four or five 

 sharp denticles and a very strong sharp tooth at the inner distal 

 angle ; the third article is the smallest of the series, stout, with a 

 very strong, acute spine at the inner distal angle and four or five 

 denticles along the brief distal margin ; the fourth antennal article 

 is widely expanded with the margin rounded and cut into nine 

 acute, triangulate teeth, the smallest of these being the inner 

 proximal one. The first three antennal articles are covered with 



