65 



37. PoTAMON (Acanthotelphusa) fungosum, Alcock. (Fig. 12.) 



The whole animal is covered with a very short, dirty, spongy fur. The 

 species is closely related to P. fece de Man. 



Carapace shghtly convex, nearly as long as broad, its depth less than half 

 its length, its surface broadly corrugated and lumpy, and much pitted when 

 denuded. 



Cervical gi'oove well graven only where it defines the mesogastric area 

 posteriorly, elsewhere very broad and superficial, and somewhat vague. 



The regions are all well defined, as well as the pair of small oval facets 

 between the gastric and cardiac regions. In the gastric region the mesogastric 

 area can be made out in most of its extent, and the ai-ea on either side of it, 

 behind the post-orbital crests, is broken into one or two low broad elevations. 

 In each epibranchial region there are two broad transverse cori-ugations, one 

 behind the other, and two small lumpy facets inside of them. 



Front hardly deflexed, more than two-fifths the greatest breadth of the 

 carapace (in the adult), its sides convergent and dorsally tumid, its free edge 

 sharp, obscurely bilobed, and much overshadowing the epistorae. 



Orbits wide, the lower border crenulate and separated from the external 

 orbital tooth by a gap, the upper border broken near the middle by a slight crease. 



Antero-lateral boi'ders of carapace about as long as the postero-lateral, cut 

 into four broad salient spines, exclusive of the outer orbital tooth ; postero- 

 lateral borders defined in all their extent by a sharp granulous ridge. 



Epigastric crests broad and blunt, much separated from and in advance of 

 the post-orbital crests ; post-orbital crests consisting of a sharp transverse 

 tubercle not extending beyond middle line of orbit, and of one or two minute 

 tubercles lying between this and the anterior marginal spine ; these small 

 tubercles may sometimes be absent. 



In the male abdomen the 6th segment is nearly twice as broad as long, 

 and the 7th is a broad-based, very blunt triangle nearly as long as broad. 



All the mouth-parts are as in P. dayanum. 



Chelipeds in both sexes markedly unequal, and, when completely denuded, 

 practically smooth, so much effaced in appearance is the superficial sculptm'e ; 

 upper border of merus with a subterminal spine ; carpus with upper surface 

 even, and with the usual spine at the inner angle. In the smaller cheliped the 

 fingers are much longer than the palm, and do not gape when closed ; in the 

 larger cheliped the fingers are not much longer than the palm, have molariform 

 teeth, and gape much when the tips are apposed. 



Legs somewhat slender, a little longer than the smaller cheliped ; the 

 propodites are more than twice as long as broad, and are not so long as the 

 slender dactyli. 



