CRUSTACEA CASPIA. 467 



almost in a brushlike manner, clothed with delicate bristles. The flagelliim 

 is likewise densely se^iferous, and only composed of 6 articulations. 



The mandibular palps (fig. 1 5) are highly remarkable for their extra- 

 ordinary size, being more than twice as long as tlie mandibles. The terminal 

 joint is fully as long as the 2nd, both being rather broad, and densely sup- 

 plied with long and curved bristles. 



The gnathopoda of the female (see the figures given by Mr. Sowinsky) 

 ai-e comparatively poorly developed, and nearly equal-sized, thereby differing 

 conspicuously from those in the female of G. Weidemanni. In tlie male, how- 

 ever, these limbs (figs. 16, 17) are much more powerful and rather unequal, 

 the posterior ones (fig. 1 7) being much the stronger. The propodos of the 

 latter is very large and broad, of oval quadrangular form, whereas in the 

 former (fig. 1 6) it is rather narrow oblong. 



The pereiopoda are almost exactly of same structure as in G. Weide- 

 manni, and need not therefore be described in detail. 



The same is also the case with the uropoda (figs. 18, 19) and the telson 

 (fig. 20). 



Occurrence. — Some specimens of this form are contained in the col- 

 lection of Dr. Grimm, but without statement of locality. It was taken 

 during the past summer in great abundance by Messrs. Andrussow and 

 Maximovicz in the bay of Karabugas, from quite shallow depth. 



Distribution. — The Azow Sea (Sowinsky). 



20. Gammarus pauxillus, Grimm. MS. 



(PI. 10, figs. 1—13). 



Specific Characters. — Body very slender and compressed. Cephalon 

 with the lateral lobes somewhat obliquely truncated, anterior corner the 

 more prominent. Coxal plates of moderate size and quite smooth. Last pair 

 of epimeral plates of metasome slightly produced at the lateral corners. 

 Urosome with a single spinule on each side of the last 2 segments. Eyes 

 rather large, oblong oval. Superior antcnnre much longer tlian the inferior, 

 flagellum very slender, accessory appendage small, triarticulate. Gnathopoda 

 in female comparatively feeble, and subequal in size; those in male very 

 powerful, with the propodos in both pairs exceedingly large, and oblong oval 

 in form. Anterior pairs of pereiopoda slender, posterior pairs moderately 

 elongated, basal joint of last pair but slightly expanded, and scarcely larger 

 than that of the penultimate pair. Last pair of uropoda rather elongated, 

 outer ramus sublinear, spinous, inner small, scale-like. Telson very short, 

 lateral lobes blunted at the tip, and without any apical spines. Lenght of 

 adult female 4 mm., of male 6 mm. 



•tHS.-MaT. CTp. 297. 47 



