298 Carcinological Fauna of India. 



a distinctly Caucroid arch : the carapace is naaally 

 much broader than long : — 



i. Dactyli of last pair of legs styliform Pseuuukhumbila. 



ii. Dactyli of last pair of legs compressed and 

 ciliated : — 



a. Antero-external angle of merns of 

 external innxillipeds not particularly 

 produced : — 



a. Carajiace transversely quadri- 

 lateral, its antero-lateral borders 



with few teeth .. Carcinoplax. 



3. Carapace transversely elliptical, 

 its antero-lateral borders with 5 



or 6 teeth Catopxrus. 



b. Autero-external angle of merus of exter- 

 nal maxillipeds strongly produced out- 

 wards : last pair of legs sometimes 



paddle-like Libystes. ^y- 



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

 than the greatest breadth of the carapace in extent, 

 so that the antero-lateral borders of tlie carapace 

 are either slightly arched or nearly straight : the 

 carapace is broader than long but is not conspiou- 

 onsly transverse :— 



i. The antennal flagelliim stands loosely in 

 orbital hiatus ; — 



a. Cai'apace deepish, rather markedly trans- 

 verse : the nieri of the legs with a 

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

 h. Carapace shallow, depressed, and flat, 

 little broader than long : — 



u. Legs spiny PlatypillMiNUs. 



0. Legs unarmed Pilumnoplax. 



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

 pletely fills up and closes the orbital hiatus, 



entirely excluding the antennal fiagellum Eucratk. 



11. Front with the edge slightly but distinctly carved, never 

 cut straight and square ; carapace and appendages in all 

 the Indian species tomentose and hairy Litochika. 



Edcrate, De Haau. 



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

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



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



Cai'apace deepisli, subquadrilateral, a little broader tliau loug, 

 smooth and with little or no distinction of I'egions, convex fore and aft, 

 very slightly t>o from side to bide. 

 ' 640 



