Ol 



crests in line with the inner angle of the outer orbital tooth. Frontal region 

 tuberculous ; anterior part of gastric region rugulose ; anterior half of 

 epibranchial regions obliquely rugose ; side-walls of carapace tuberculous 

 anteriorly (as are the well-defined suborbital lobes) and obliquely rippled 

 posteriorly, the ripplings extending well across the postero-lateral borders. 



The epigastric crests, though separated from the post-orbital crests on 

 either side by a break, form the convexity of a common curve with the latter, 

 which are crenulate and incline well forwards beyond the point of intersection 

 by the cervical groove. 



Front declivous, faintly and broadly bilobed in a dorsal view, its breadth 

 in the adult considerably less than a third the greatest breadth of the carapace, 

 its edge (like that of the orbit) well-defined and crenulate. Upper edge of 

 orbit sinuous ; external orbital tooth prominent, subacute, and separated from 

 the lower border of the orbit by a gajD. 



Antero-lateral borders of carapace hardly as long as the postero-lateral, 

 raised, serrulate, well-arched, the curve running on to the dorsum of the cara- 

 pace posteriorly ; epibranchial tooth not pre-eminent above the general serration. 



In the adult male abdomen the length of the 6th segment is nearer half 

 than two-thirds its greatest breadth, and is sometimes not more than half; 

 that of the 7th segment is decidedly less than its greatest breadth. 



Antennular fossae narrow : inter-antennular septum very broad. 



First (true 2nd) antennal joint broad, squarish, the two succeeding 

 joints covered by and in contact with the front. 



Mandibles and maxiUipeds not appreciably different from those of 

 P. fluviatile var. ibericum, except that the antero-external angle of the mei'us 

 of the external maxiUipeds is not so well rounded oft". 



The cheHpeds are quite like those of P. atkinsonianum, the whole of the 

 upper and outer surface of the palm and a good deal of the inner surface of 

 the palm being rugose, and the upper border of the dactylus being tuberculous 

 or denticulate in its basal half. 



The legs also resemble those of P. atkinsonianum, but are more slender, 

 the propodite of the 2nd and 3rd pairs being from two and a half to nearly 

 three times as long as broad. 



The carapace of the largest specimen is If inch long, and 1+f inch broad— 

 a male. 



I name the species bifarium, as its local habitation, recorded on its label, 

 is double, or doubtful. 



551^. Sikkim or Burma. W. T. Blanford. 6 <?. 



10 



The species may, perhaps, be only a variety of P. atkinsonianum, but its 

 convex carapace and comparatively slender legs seem to be valid marks 

 of distinction. 



