]900.] A. Alcock — Carcinoloyical Fauna of India. 299 



The extent of the fronto -orbital border is not much less than the 

 greatest breadth of the carapace, the antero-lateral borders therefore, 

 which are toothed, are short and but slightly arched. Front square-cut 

 and straight, well delimited from the well-defined supra-orbital angles, 

 usually notched or grooved in the middle line, about a third the breadth 

 of the carapace. 



Upper border of orbit with two distinct sutures. The orbital hiatus 

 is compactly filled and closed by a process of the basal antenna-joint, bo 

 that the antennal flagellnm, which is of good length, lies entirely outside 

 the hiatus. The antennules fold transversely. 



Buccal cavern square, completely closed by the external maxillipeds, 

 the flagellum of which articulates with the inner angle of the merus. 

 Efferent branchial channels of palate well defined. 



Chelipeds subequal, much more massive and shorter, or not much 

 longer, than the legs. 



Legs slender, unarmed ; the propodite and dactylus of the last pair 

 are compressed and are usually, but not always, somewhat broadened. 



In both sexes all seven abdominal segments are distinct, and in the 

 male the third segment covers the whole width of the sternum between 

 the bases of the last pair of legs. 



Distribution: Indo-Pacific (Indian, Australian and Japanese). 



Following de Man and Ortmann, I restrict the genus Eucrate to 

 those species in which the orbital hiatus is completely stopped-up by a 

 process of the basal antenna-joint. 



Key to the Indian species of the genus Eucrate. 



I. Antero-lateral borders of the carapace cut into four 

 teeth (including the outer orbital angle) all of 

 which are distinct : dactylus of last pair of legs 

 distinctly palmulate : front grooved or notched in 

 the middle line : — 



1. Carapace nearly smooth E. crenata. 



2. Carapace with some short transverse ridges 



in its antero-lateral part E. crenata var. ajfinis. 



II. Antero-lateral borders cut into four teeth (including 

 the orbital angle) of which the 2nd and 4th are 

 hardly distinguishable : front with the median 

 notch almost obsolete : dactylus of last pair of legs 



palmulate E. crenata var. den lata. 



III. Antero-lateral borders cut into three teeth (includ- 

 - ing the orbital angle) : dactylus of last pair of legs 



almost styliform E. sezdentata. 



