T. XIIl] ' CRUSTACEA CASPIA. 493 



having the dorsal face somewhat more arched. As seen from above (fig. 1), 

 it appears much less attenuated in front, thus approaching to a claviform 

 shape. 



The carapace is comparatively considerably larger than in the female, 

 exceeding in length the exposed part of the trunk, and has the branchial 

 regions somewhat more swollen, whereas the pseudo-rostral lamellae appear 

 shorter and more obtuse. Below them there is scarcely any sinus (see fig. 2), 

 the anterior edges being obliquely truncated, with the antero-lateral corners 

 obtusangular. The latter are considerably more expanded laterally than in 

 the female, so as to be wholly visible in the dorsal view of the animal (figs. 

 1 and 3). The crests running along the branchial regions and the gastric 

 area are less sharply defined and quite smooth. Finally the ocular lobe 

 (see fig. 3) appears less broad, and has the lateral corners more evenly 

 rounded. 



The free segments of the mesosome are comparatively narrower than in 

 the female, the 3rd segment especially being very short in its dorsal part. 

 The epimera are, as usual in male specimens, more prominent laterally, and 

 those of the last segment terminate posteriorly in a conical projection. 



The metasome is very much elongated, considerably exceeding in length 

 the anterior division of the body, and has the 2 anterior segments compara- 

 tively thicker than in the female. 



The eye (see fig. 3) is very fully developed, exhibiting, in addition to 

 the lateral cornea?, another median one; all the cornea? are very distinctly 

 defined and highly refractive. 



The superior antenna? (fig. 4) have the flagella modified in the usual 

 manner. 



The inferior antenna? (see figs. 1 and 2) do not nearly attain the length 

 of the body; otherwise they are built in the very same manner as in the 

 other species. 



The 1st pair of legs (fig. 5) have the basal joint considerably curved, 

 and much dilated in its proximal part, to receive the strong muscles moving 

 the exopodite. It has a double series of plumose seta?, one along the interior 

 edge, the other along the lateral crest running along the joint. 



The 2nd pair of legs (fig. 6) appear rather unlike those in the female, being 

 much larger and more densely setiferous. The carpal joint is considerably 

 prolonged, being more than twice as long as the 2 preceding joints combined, 

 and is edged on both sides with numerous short plumose seta?. The terminal 

 joint is somewhat curved, and armed in its outer part with 5 recurved hooks. 



The 2 succeeding pairs (fig. 7) are modified in the usual manner, having 

 the basal joint very large and expanded, and the exopodite well developed. 



Bnlletiu N. S. IV (XXXVI) p. 329. 35 



