298 A. Alcock — Carcinoloyical Fauna of India. [No. 3, 



a distinctly Cancroid arch : the carapace is usually 

 much broader than long : — 



i. Dactyli of last pair of legs styliform , Pseudorhombila. 



ii. Dactyli of last pair of legs compressed and 

 ciliated : — 



a. Antero-external angle of merus of 

 external maxillipeds not particularly 

 produced : — 



a. Carapace transversely quadri- 

 lateral, its anterolateral borders 



with few teeth Carcinoplax. 



)8. Carapace transversely elliptical, 

 its anterolateral borders with 5 



or 6 teeth Catoptrus. 



h. Antero-external angle of merus of exter- 

 nal maxillipeds strongly produced out- 

 wards : last pair of legs sometimes 



paddle-like Libystes. 



2. The fronto-orbital border is not so very much less 

 than the greatest breadth of the carapace in extent, 

 so that the antero-lateral borders of the carapace 

 are either slightly arched or nearly straight : the 

 carapace is broader than long but is not conspicu- 

 ously transverse :— 



i. The antennal flagellum stands loosely in 

 orbital hiatus : — 



a. Carapace deepish, rather markedly trans- 

 verse : the meri of the legs with a 



spine or spines on the anterior border ... Psopheticus. 



b. Carapace shallow, depressed, and flat, 

 little broader than long : — 



a. Legs spiny Platypilumnus. 



&. Legs unarmed Pilumnoplax. 



ii. A process of the basal antenna- joint com- 

 pletely fills up and closes the orbital hiatus, 



entirely excluding the antennal flagellum Eucrate. 



II. Front with the edge slightly but distinctly curved, never 

 cut straight and square ; carapace and appendages in all 

 the Indian species tomentose and hairy Litochira. 



Eucrate, De Haan. 



Eucrate, De Haan, Faun. Japon. Crust, p. 36: de Man, Journ. Linn. Soc, Zool., 

 1887-88, p. 88 : Ortmann, Zool. Jahrb., Syst. VII. 1893-94, p. 685. 



Heteroplax, Stimpson, Proc. Ac. Nat. Sci. Philad. 1858 (1859) p. 94. 



Carapace deepish, subquadrilateral, a little broader than loug, 

 smooth and with little or no distinction of regions, convex fore and aft, 

 very slightly so from side to side. 



