CRUSTACEA CASPIA. 449 



such spines. Lateral lobes of cephalon somewliat prominent, and obtusely 

 truncated at tlie tip. Coxal plates not very large, somewliat deeper in female 

 than in male. Last paii- of epimeral plates of metasome acutely produced at 

 the lateral corners. Eyes oblong oval. Superior antennae much longer than 

 the inferior, and very slender, flagellum fully twice the length of tlie ped- 

 uncle, accessory appendage rather elongated, and composed of 5 — 7 articu- 

 lations. Guatliopoda rather unequally developed, the posterior ones being 

 much the stronger, and in male exceedingly powerful, witli the propodos 

 large and tumefied. Pereiopoda comparatively more slender tlian in most 

 other species, basal joint of the 3 posterior pairs rather narrow, that of 

 last pair oblong quadrangular in form, being produced at the infero-posteal 

 corner to a short narrowly rounded lobe. Last pair of uropoda very much 

 elongated, outer ramus narrow, sublinear and densely setons, inner ramus 

 small, scale-like. Telsou with the lateral lobes conically tapering, aud each 

 armed with 2 apical spines. Length of male 27 mm. 



Remarks. — The present form was labelled by Dr. Grimm G. robiistus; 

 but, as this name has been already appropriated by Prof. S. Smith for an 

 American species, I have seen fit to change it, and to name the species 

 after its discoverer. It is very nearly allied to the form described by the 

 present author in his first article on the Caspian Amphipoda as G. hcemo- 

 baphes Eichwald, and at first 1 was indeed inclined to regard it only as a 

 variety of that species. On a closer examination, however, I have found it 

 to differ rather conspicuously in some particulars, so as more properly to be 

 regarded as specifically distinct. 



Description. — The length of the largest specimens reaches to 27 mm., 

 and this form accordingly grows to a considerably larger size than G. hcsmo- 

 baphes. As usual, male specimens are generally larger than female ones. 



The body (see fig. 1 ), as compared witli that of G. hcEmobaphes. appears 

 rather more slender and compressed, and has the mesosome and metasome 

 quite smootli throughout. The urosome, on the other hand, has each of its 

 first 2 segments produced dorsally to a very prominent uarrow tu])ercle of 

 a similar shape to that found in G. caspius. Tlic tubercle of the 1st segment 

 (see fig. 3) is somewhat stronger than tliat of the 2nd, and carries on tlie 

 transversely truncated tip, 4 spines arranged in pairs, and accompanied by 

 a few small hairs. The posterior tubercle bas only 2 juxtaposed apical spines. 

 Moreover, the 1st segment has 2 unequal lateral spinules, and 3 similar 

 spines occur on each side of the last segment, at the base of the telsou. 



Tlie cephalon scarcely attains the length of the first 2 segments of the 

 mesosome combined, and has the lateral lobes rather broad and somewliat 

 prominent, with the tip obtusely truncated. 



*u3.-M:iT. CTp. 279. 29 



