372 Carcinological Fauna of India. 



prominent tootli. The merus of the external maxilh'peds is grooved' 

 along the outer border. 



Chelipeds in the male nearly three times the length o£ the carapace : 

 wrist elongate, someAvhat cuboid, with a strong laterally-compressed 

 lobe or tooth at its inner angle : palm rather high, both borders 

 marginate and a second fine I'idge runs close to and parallel with the 

 lower border : fingers a little shorter than the palm, finely denti- 

 culate. 



In the female the chelipeds are not twice the length of the cara- 

 pace, the wrist is not elongate, though the tooth at its inner angle is 

 present, and the fingers are a little longer than the palm. 



The meropodites of the legs are slightly dilated, the dactyli ai'e 

 shorter than the propodites, and the carpopodites and pi'opodites of the 

 first two pairs are densely tomentose. 



The fifth abdominal tergum of the male, though not particularly 

 elongate, is a little constricted at base. 



In the Indian Museum are 6 specimens from Mergui. The carapace, 

 of the lai'gest is 4 millim. long and 5 millim. broad. 



Subfamily Macrophthalmin^, Dana. 



Clistostoma, De Haan restr. 



Cleistostotna ( — dilata -nee pusillajDe'Eaari, Faun. SuYiOJi. Crust, p. 26: Milne 

 Edwards, Ann. Sci. Nat., Zool., (3) XVIII. 1852, p. 160. 



Carapace of no great depth, broader than long, its sides slightly 

 arched, its regions ill-defined. 



Front of moderate breadth, more than a fourth the greatest breadth 

 of the carapace, declivous : orbits well defined, of good depth, occupying 

 all the rest of the anterior border of the carapace : eyestalks stout, eyes 

 terminal. The antennules fold obliquely: the antennaa are small and 

 stand in the inner orbital hiatus. 



Epistome well defined, very short fore and aft, with a prominent 

 lobe or tooth in the middle line' projecting between the extei'nal 

 maxillipeds. 



Buccal cavern squarish, but with the sides a little arched, com- 

 pletely closed by the external maxillipeds. These are large, and have 

 the inner angle of the ischium strongly produced, the merus as large as 

 or larger than the ischium, and the palp articulating at the antero- 

 external angle of the merus : the carpus is ovate, but the two terminal 

 joints are very short and slender: the exognath is in great part con- 

 cealed. 



Chelipeds in the female shorter and slenderer than any of the legs, 

 in form exactly like those of the female of Gelasimus. 



714 



