52 



tlie cervical groove as they are in all the preceding species except P. larnaudii 

 and brevimarginatum. 



In the male abdomen the length of the 6th segment is between half and 

 two-thirds its greatest breadth ; that of the 7th is equal to its greatest breadth. 



The antennpe and mouth-parts are normal ; the merus of the external 

 maxillipeds is a httle broader than long. 



The chelipeds are subequal ; the outer surface of the merus and carpus is 

 crisply rugulose, the rugse being elegantly beaded ; the outer surface of the 

 palm and the lower part of its inner surface are studded with shiny conical 

 granules, often in pairs ; the inner angle of the carpus is produced into the 

 usual bicuspid spine : the fingers are longer than the palm, and they hardly 

 gape when closed. 



Legs about as long as the chelipeds ; their dactyli are much longer than 

 their propodites, and in the 2nd and 3rd pairs the propodites are two and a half 

 times as long as broad. 



In the largest specimen, a female, the carapace is 1 fv inch long, If V inch 

 broad, and }''ths inch deep. 



6723 ^ r ^ 



~~r~ • 7 immature $ , 1 ? , 1 2 young. 



c^Do ■ Tavov. Museum Collector. I 



5488 •' o ■ » o 



1 immature V ■ 

 10 J \ 



5531 ( Hills between Burma 1 ,, ,-^ ■, * -, r^ ■ 



, „ ■ , c- Uonor {.O. 1 (J, 1 V immature. 



10 I 'ind hiam. j ^ ^ ^ ' ■^ 



27. PoTAMON (Potamon) turgidulimanus, Alcock. (Fig. 9.) 



This small species is distinguished by the absence of any gap between the 

 external orbital tooth and the lower border of the orbit. I regard this as a 

 character of some importance, as this gap is almost characteristic of Potamon, 

 and its absence is almost characteristic of Paratelplmsa — not that this species 

 has anything to do with the latter genus. Another character is that the palms, 

 especially that of the larger cheliped, have a fullness or puffiness of the lower 

 part of the outer surface. 



The cervical groove and the areolation of the epibranchial regions are 

 almost as distinct as in bretyimarginatum. 



The frontal region, the epigastric and post-orbital crests, and the anterior 

 half of the gastric and epibranchial regions are rugulose as in brevimarginatum. 



The epigastric crests sometimes form an almost straight line with the post- 

 orbital crests as in pruinosum, and sometimes are slightly advanced and oblique. 



The antero-lateral borders of the carapace are slightly longer than in 

 breinmarginatum. 



The chelipeds are sometimes as crisply rugose as those of bremmarginatwn 

 and prmnosiim, but sometimes the sculpture looks worn and effaced. 



