87 



14. Paratelphusa (Barytelphusa) guerini, Milne Edwai'ds. 



(Fig. 57.) 



Telphimi iiuenni, Milne Edwards, Ann. Sci. Nat. Zool. (3), XX., 1853, p. 210. 



Potamon\Potainonautes)gmrim, Mary J. Rathbun, Nouv. Archiv. du Museum (4), VII., 1905, p. 186 («W 

 lit.), pi. xvi., fig. 2. 



Carapace broad, deepish, and strongly convex ; its length in the adult 

 male is about two-thirds its greatest breadth, but is more than two-thirds in 

 the adult female ; its depth is half its length, or more ; its surface is, to the 

 naked eye, smooth, except for a few short faintish rugse just inside the lateral 

 borders. 



Cervical groove broad and deep, running towards but not reaching the 

 site of the lateral epibranchial tooth. 



Except for the longitudinal mesogastric furrow the regions of the carapace 

 are not areolated. 



Front, in adults, more than a fourth the greatest breadth of the 

 carapace, much deflexed, rather square-cut, although its sides are con- 

 vergent and its smooth edge is feebly bilobed ; its sm-face, though smooth, is 

 tumid. 



Orbits wide, with a smooth edge ; the outer orbital angle is very broad, 

 low, and blunt, and there is no distinct gap ventral of it. 



Antero-lateral borders of carapace strongly convex, well defined, bluntly 

 and rather irregularly crenulate ; the lateral epibranchial tooth and notch are 

 only just discernible at the best of times. 



The epigastric and post-orbital crests form one bold ridge on either side of 

 the mesogastric furrow, the epigastric portion being distinguished by its 

 bluntness and greater thickness ; the crest ends on the dorsum of the carapace 

 ivell behind the site of the lateral epibranchial tooth, and it is not anywhere cut 

 by the cervical groove. 



In the male abdomen the 6th segment is long (its length almost equal to 

 its greatest breadth), but the sides are distinctly convergent; the blunt 7th 

 segment is longer than broad. 



The mouth-parts are as described in jacquemontii, the only noteworthy 

 difference is that the merus of the external maxillipeds is, as in cwnicularis, 

 more quadrangular in outline. 



Chelipeds much more unequal in the male than they are in the female ; 

 much as described in jacquemontii, with the modifications noticed in cwnicularis 

 —that is to say, the fingers, particularly the fixed finger, are broader, and none 

 of the teeth is remarkably enlarged. 



Legs as described in jacquemontii. 



