CRUSTACEA CASPIA. 205 



The inferior antenuse (see fig. 1) are much shorter than the superior, 

 scarcelj' exceeding half their k;ngtli. They are constructed in the usual 

 manner, exhibiting^ a large globular basal joint followed by two short and 

 2 elongated i^eduncular joints. The flagellum considerably exceeds half the 

 length of the peduncle, and is composed of about 12 articulations. 



The buccal area (see fig. 1) is rather projecting, being only partly ob- 

 tected by the 1st pair of coxal plates. The several oral parts (figs. 4—10) 

 composing it, are quite normal in their structure, and need not therefore to 

 be described in detail. 



The gnathopoda (figs. 11 and 12) are rather small and nearly of equal 

 length, though the posterior ones (fig. 12) appear somewhat more slender 

 than the anterior. Both pairs are rather richly supplied with bristles, partly 

 arranged in dense fascicles, especially on the lower edge of the carpus and 

 propodos. The latter appears in the anterior pair (fig. 11) somewhat broader 

 and more expanded distally than in the posterior pair, where it (see fig. 1 2) 

 exhibits a rather narrow oblong oval form. The palm in both pairs is some- 

 what oblique, being defined below by an obtuse angle carrying a pair of 

 short spines. 



The pereiopoda are of moderate length and rather strongly built, having 

 their outer part edged with fascicles of stiff bristles intermingled with 

 spines, especially at the end of the raeral and carpal joints. In all of them 

 the dactylus is very strong, terminating in a sharp curved point. The 2 

 anterior pairs are, as usual, of the same structure, though somewhat unequal 

 in length, the 2nd pair (fig. 13) being a little shorter than the 1st. 



Of the 3 posterior pairs the penultimate ones (fig. 1 5) are the longest, 

 and have the basal joint oval in form, with the posterior edge but very 

 slightly curved. In the antepenultimate pair (fig. 14) the basal joint is some- 

 what smaller, but otherwise of a much similar form, being in both pairs 

 broadest in its proximal part and somewhat narrowed distally. The last pair 

 (fig. 16) differ considerably from the others in the form of the basal joint, 

 which is very broad, forming posteriorly a large, laminar expansion termi- 

 nating below in a broadly rounded lobe which extends beyond the ischial 

 joint. The edges of the expansion are minutely serrate, with small bristles 

 springing of from the serrations, and having between them a very fine 

 ciliation. 



The branchial and inbubatory lamelte (see fig. 12) exhibit a similar 

 structure to that in the 2 preceding genera. 



The uropoda successively decrease in size, the 1st pair (fig. 17) being 

 rather large and about twice as long as the 2nd (fig. 18). In both pairs the 

 basal part as also the rami are coarsely spinous, the latter being subequal 



$H3.-MaT. CTp. 205. 27 



