(!RUSTACEA CASPIA. . 465 



The outer ramus is about twice as long as the basal part, and rather broad, 

 sub-foliaceous, being edged all round with slender, ciliated setae, and having 

 moreover 2 fascicles of spines on the outer edge. Its terminal joint is so 

 very minute, as easily to escape attention. The inner ramus is of larger size 

 than usual, being fully lialf as long as the outer, and is provided inside witli 

 2 juxtaposed spines, followed by a regular row of slender bristles. 



The telson (fig. 11) is cleft by a deep incision, somewhat widening post- 

 eriorly, into 2 rather narrow lobes, each of wliich carries, on the somewhat 

 blunted tip, 3 spines. 



Occurrence. — Of tliis form at tirst but a few specimens, collected by 

 Mr. Weidemann, were sent me from ihe Zoological Museum. The same 

 form was subsequently found rather plentiful in some collections made by 

 Messrs. Andrussow and Maximowicz in the bay Karabugas. It here 

 occurred together with G. maeoticus at a short distance from the shore, on 

 a sandy bottom. A few specimens of the same form were also collected by 

 Mr. Warpachowsky in the eastern part of the North Caspian Sea, at 

 Stat. 63. 



19. Gammarus maeoticus, Sowinsky. 



(PI. 9, figs. 12—20). 



Gammarus maeoticus., Sowinsky, LesCrustacesdelamerd'Azow, 

 p. 6, PI. I, A, PI. II. 



Specific Characters. — Very like the preceding species, as to its out- 

 ward appearance. Cephalon, liowever, having the lateral lobes more promi- 

 nent, and narrowly rounded at the tip. Anterior pairs of coxal plates com- 

 paratively smaller and rapidly diminishing in size anteriorly; 1st pair not at 

 all expanded distally. Last pair of epimeral plates of metasome nearly rect- 

 angular. Urosome smooth above. Eyes comparatively small, reniform. 

 Antennae more robust than in the preceding species, flagellum of the super- 

 ior ones scarcely as long as the peduncle, accessory appendage almost half 

 the length of the fl.i"""^'iim, and 5-articulate. Inferior antennae with the 3 

 outer joints of the ])eduncle rather broad, forming posteriorly rounded ex- 

 pansions, densely clothed with delicate bristles. Mandibular palps exceedingly 

 large, more than twice the length of the mandibles. Gnathopoda in female 

 comparatively small and feeble, nearly equal-sized; in male much more 

 powerfully developed, and rather unequal, the posterior ones being much 

 the larger. Pereiopoda, uropoda and telson nearly agreeing in structure with 

 those parts in G. Weideinanni. Length of adult male 1 2 mm. 



Bemarks. — This species was detected by Mr. Sowiusky in the Azow 

 Sea, and the female was rather fully described by him in a Russian paper 



•I'lis.-MaT. CTp. 295. 45 



