(xxxv1)] CRUSTACEA CASPIA, 333 
the 2 preceding species deeply cleft in the middle, its lateral halves somewhat 
projecting and obtusely rounded at the tip; antero-lateral corners nearly 
rectangular. Exposed part of trunk without any keel or projections, its last 
segment comparatively small. Metasome poorly developed, scarcely attaining 
the length of the anterior division of the body. Eye well developed, with all 
3 cornes distinct. Antenne and legs apparently of the normal structure. 
Uropoda comparatively small, with the rami equal-sized and exceeding 
the scape in length, each terminating in a rather strong spine, the inner one 
minutely serrated inside. Telson semicircular. Length of adult female . 
scarcely exceeding 3 mm. 
Remarks. — This is a very distinct species, easily recognizable by the 
unusually short and stout form of body, the scabrous integuments and the 
shape of the carapace. 
Description of the female. 
The solitary specimen examined, a fully grown ovigerous female, does 
not exceed a length of 3 mm, and this form belongs thus to the smaller 
species of the genus. 
The general form of the body (see figs. 12 and 13) is exceedingly short 
and stout, more so than in any of the other known species, and the 2 chief 
divisions appear very sharply marked off from each other. The anterior 
division is rather tumid and of an ovoid form, with the greatest breadth 
about in the middle. As seen from above (fig. 11), it tapers gradually both 
anteriorly and posteriorly. In a lateral aspect (fig. 12), the dorsal face ap- 
pears gently arched, and the anterior extremity somewhat truncated. 
The integuments are rather strongly incrusted, and exhibit everywhere 
a distinct squamous structure, the squamulæ being elevated to small pro- 
jecting spikes, thus giving the surface a scabrous character. 
The carapace is comparatively large and deep, exceeding in length the 
exposed part of the trunk, and exhibits, as seen from the side (fig. 12), a 
Somewhat quadrangular form, with the upper contour nearly horizontal, 
though somewhat interrupted in the middle by the projecting branchial 
regions. In a dorsal view (fig. 11), it has its greatest breadth quite posteriorly, 
and appears somewhat instricted in the middle. The branchial regions are 
distinctly defined and, as in the 2 preceding species, very sharply marked off 
in front from the gastric area. The latter is flattened, without any distinct 
| keels, and terminates in front in a well defined, though rather short and 
_ broad ocular lobe. On each side of the gastric region a very conspicuous 
horizontal crest runs forwards, terminating at the tip of the pseudo-rostral 
Projection. The latter appears, when the animal is viewed from the side 
Mélanges biologiques. T. XIII, p. 497. 
