(xxxv1)] CRUSTACEA CASPIA. 317 
The gnathopoda (figs. 4 and 5) are likewise somewhat more robust, 
especially the posterior ones (fig. 5), though otherwise exhibiting the struc- 
ture characteristic of the genus. 
As to the legs (figs. 6— 10), they are on the whole much more strongly 
built than in the 3 preceding species. On the 1st pair (fig. 6) the basal joint 
is scarcely longer than the 4 succeeding joints combined, and the latter are 
comparatively broader and more laminar than in those species, whereas the 
terminal joint has conserved its narrow linear form unaltered. 
The 2nd pair of legs (fig. 7) are much curved and extremely robust, other- 
wise of the usual structure. 
The 3 posterior pairs of legs (figs. 8—10) likewise exhibit an unusually 
robust appearance, and are distinguished by the large size of the meral 
joint, which is fully twice as long as the carpal one. The dactylar joint, 
moreover, is unusually strong and claw-like, whereas the modified setze 
issuing from the 2 preceding joints are comparatively short. The rudimen- 
tary exopodite, present in the penultimate and antepenultimate pairs, is very 
small, though consisting of 2 well-defined articulations and carrying the 2 
usual, plumose sete (see figs. 8 and 8 a). 
The uropoda (see fig. 11) are comparatively short and stout, scarcely 
exceeding in length 14 of the metasome. The Scape is rather massive, and 
provided on the inner edge with 4 strong spines. The rami are very uncqual, 
the inner one being by far the larger and about the length of the scape. It 
carries on the inner edge 4 short spines and on the tip 2 unequal ones, the 
outer of which is about half as long as the ramus. The outer ramus is about 
*/, the length of the inner, and terminates with 2 very unequal, slender spines, 
the inner of which attains the length of the whole ramus; it moreover car- 
ries on both sides, near the tip, a small seta. 
The telson (ibid. fig. 12) is very small, and exhibits a nearly semicircu- 
lar form, the tip being evenly rounded. 
Description of the male, 
(Pl. VI) 
The length of adult male specimens docs not exceed that of the female. 
The general appearance is, however, rather different (see figs. 1 and 2), the 
body being comparatively much more slender, with the anterior division not 
nearly so tumid, and also less boldly vaulted above. The carapace exhibits a 
Somewhat different form, being less attenuated in front, and having the 
pseudo-rostral projection shorter and more obtuse, whereas the antero-lateral 
corners are much more prominent and nearly rectangular. 
Melanges biologiques. T. XIII, p. 481. 
