358 G. 0. SARS, 



to be found, partly collected at Baku from stones on the shore, jiartly on 

 the west coast of Sara, among Zostera. 



13. Gammarus robustoides, Grimm MS. 



(PI. XII). 



Syn.: ? Gammarus caspius, Sp. Bate (not Pallas) 

 Gammarus aralo-caspiiis, Grimm MS. 



Specific Characters. — Body rather strongly built and but little com- 

 pressed, the back being broadly rounded. Lateral lobes of cephalon rather 

 projecting and somewhat obliquely truncated at the tip, the lower corner 

 being more prominent than the upper. Anterior pairs of coxal plates of 

 moderate size, and densely fringed with bristles on their distal edge; 1st 

 pair but very slightly widening distally; 4th pair scarcely as broad as they 

 are deep. The last 2 pairs of epimeral plates of metasome acutely produced- 

 at the lateral corners. Urosome with the 2 anterior segments forming each 

 at the end doi'sally a slight protuberance armed with a number of densely 

 crowded spines arranged in an angularly bent transverse row, the 1st seg- 

 ment having generally 8 such spines, the 2nd 6 ; last segment with a dorsal 

 fascicle of delicate hairs, and having besides on either side of the dorsal face 

 2 spinules. Eyes of moderate size and oval reniforra in shape. Antennae 

 comparatively short and nearly equal-sized, the superior ones with the 1st 

 joint of the peduncle rather large, fiagellum somewhat exceeding the ped- 

 uncle in length and composed of numerous short articulations, accessory ap- 

 pendage well developed, 6 — 8-articulate. Gnathopoda in female moderately 

 strong and somewhat unequal, the posterior ones being the larger, carpus 

 in both pairs rather short, propodos well developed, with the palm some- 

 what oblique; those in male considerably more strongly built than in female, 

 with the propodos, especially of the posterior ones, very large and tumid. 

 Anterior pairs of pereiopoda rather robust, and very densely setiferous, with 

 the meral joint large and expanded; the 3 posterior pairs moderately slender, 

 and having their outer part clothed with numerous fascicles of bristles and 

 scattered spines; basal joint of last pair oblong oval in form, being some- 

 what broader in female than in male, hind edge densely fringed with short 

 bristles, infero-posteal corner produced to a short, narrowly rounded lobe. 

 Last pair of uropoda of moderate size, with the inner ramus very small, outer 

 one well developed and densely fringed with slender, partly ciliated setae, 

 terminal joint extremely minute. Telson about as long as it is broad, each 

 half witli 3 or 4 apical spines. Length of adult female 17 mm., of male 

 reaching 22 mm. 



*a3.-MaT. CTp. 338. xg 



