CRUSTACEA CASPIA. 103 



exceeding in length V of the body, joints of the peduncle successively de- 

 creasing in size, flagellum but little longer tlian the peduncle, accessory 

 appendage not attaining the lengtli of the 1st articulatiou of the flagelluni. 

 Guathopoda in female somewhat unequal, the posterior ones being a little 

 more slender, and having the propodos narrower; those in male much larger, 

 with the propodos oblong oval in form, palm concave and defined below by 

 a nearly rectangular projection armed with 2 strong spines, dactylus very 

 strong and curved. The 3 posterior pairs of pereiopoda comparatively short 

 and stout, and having their outer ]iart edged with scattered fascicles of 

 spines aud delicate bristles, basal joint of the 2 anterior pairs rather small 

 and tapering distally, that of last pair oblong quadrangular in shape. Last 

 pair of uropoda rather fully developed and projecting far beyond the others, 

 outer ramus very large, pronouncedly foliaceous and edged vnth slender 

 spines and delicate bristles, tip blunt, witli a very small terminal joint. 

 Telson rather large, projecting beyond the basal part of the last pair of 

 uropoda, cleft extending nearly to the base, terminal lobes obtusely pointed, 

 and carrying each a single apical spine and a few delicate bristles. Length 

 of adult female 12 mm., of male 16 mm. 



Remarks. — The present foi'm is at once recognized by its extremely 

 slender and narrow body, on which cause I at first noted it under the pro- 

 visional uame Palasiella macera. The pronounced foliaceous character of 

 the outer ramus of the last pair of uropoda may also serve for distinguishing 

 this form from most of the other Caspian Amphipoda. It is the form upon 

 which Dr. Grimm founded his genus Gmelina. 



Description of tiie Temale. 



Fully adult, ovigerous specimens attain a length of about 12 mm. 



The general form of the body (see fig. 1 ) is very slender and highly 

 compressed, the raetasome and urosome being both well developed and com- 

 bined about the length of the mesosome. The integuments are highly in- 

 crusted, exhibiting in some places, for instance in the anterior part of the 

 coxal plates (see fig. 11) conspicuous rounded indurations. All the segments 

 are very sharply marked off from each other, whereby the outer contours 

 of the body acquire, both in the lateral and dorsal view of the animal, a 

 somewhat rugged appearance. The segments of the mesosome have their 

 lateral parts slightly prominent at the juucti(m of the coxal plates, forming 

 together an obtuse keel extending along each side of that division of the 

 body. Another keel runs along the back, being anteriorly rather low, but 

 gradually becoming more distinct backwards, and being at the same time 

 successively elevated in the segments to more or less conspicuous dorsal 



*u3.-MaT. CTp. 193. 15 13 



