428 A. Alcock — Carcinological Fauna of India. [No. 3, 



Front a little more than half the breadth of the carapace, vertical, 

 deep, somewhat spathulate, the free edge convex and very slightly 

 sinuous. 



Sides of the carapace slightly curved and convergent posteriorly, 

 no tooth behind the outer orbital angle. 



The chelipeds are longer and more massive in the male, but are 

 otherwise similar in both sexes : in the male they are less than 1| times 

 the length of the carapace. To the naked eye they are smooth, except 

 for a patch of vesiculous granules in the middle of the inner surface 

 of the palm. The inner angle of the wrist is sharply pronounced, and 

 the upper border of the palm and of the base of the dactylus have a 

 few small blunt serrulations. The palm is as high as long, the dactylus 

 is about If times the length of the upper border of the palm, the 

 fingers, though a little hollowed at tip, are subacute and have no gap 

 between them when closed. 



Legs rather slender, smooth and unarmed to the naked eye : the 

 meropodites are not broadened : the dactyli are as long as their pro- 

 podites and like them are fringed with dark spine-like bristles. The 

 3rd pair of legs, which are the lougest, are less than twice the length 

 of the carapace. 



In the Indian Museum are 61 specimens from the Andamans and 

 Nicobars, Mergui, Ganges Delta, Madras, and Minnikoy (Laccadives). 

 Many of the specimens were taken on land, hiding under timber, in 

 which situation their curious mottled coloration must be protective. 

 The largest specimen has a carapace 14 millim. long by nearly 17 broad. 



Clistocceloma, A. M. Edw. 



Clistocceloma, A. Milne Edwards, Nonv. Archiv. du Mus. IX. 1873, p. 310: 

 Kingsley, Proc. Ac. Nat. Sci. Philad. 1880, p. 219. 



Differs from Sesarma only in the following characters : — 



(1) the tooth at the inner angle of the lower border of the orbit 

 meets the frout, as in Metasesarma, so as to completely exclude the 

 antennaB from the orbit : 



(2) the reticulation of the sidewalls of the carapace resembles 

 that of Sesarma, but, on denudation, the lines of granules are found to 

 be absent, so that the meshwork is made up of hairs entirely : 



(3) the merus of the external maxillipeds is shorter. 



From Metasesarma this genus is distinguished by the lobulation of 

 the dorsum of the carapace and the dentate lateral boiders. 



If Metasesarma is to be classed as a subgenus of Sesarma as it has 

 been, and with undoubted reason, by Dr. de Man, the same course 

 might be taken with Clistocoeloma. 



