Carclnologtcal Fauna of India. 197 



three tubercles, disposed in a triangle, on the gastric region ; (3) by 

 the larger and more prominent eyes ; (4) by the absence of the lobule 

 on either side of the posterior border of the carapace ; (5) by the muck 

 more massive chelipeds of the male. 



This species is included in the Indian Fauna on the authority of 

 Prof. J. R. Henderson. There are no specimens in the Indian Museum, 



Mensethius, Edw, 



Mensethius, Milne-Edwards, Hist. Nat. Crust. L 338. 



Mensethius, Miers, Journ. Linn. Soc, Zool., Vol. XIV. 1879, p. 649; and ' Challen- 

 ger ' Brachyura, p. 36. 



Carapace subpyriform, moderately convex, and tuberculated on 

 the dorsal surface, with a large triangulate prse-oeular spine, but no 

 post-ocular spine. Rostrum simple, slender, acute, or emarginate at 

 apex. Post-abdomen in the male seven-jointed, in the female usually 

 five-jointed, the penultimate joint formed by the coalescence of three 

 segments. Eyes small, mobile, but not perfectly retractile. Basal 

 antenna! joint slightly wider at the base than at the distal extremity, 

 which is unarmed ; flagellum exposed and visible from above at the 

 side of the rostrum. Merus of the exterior maxillipedes truncated at 

 the distal extremity and with a prominent antero-external angle, and 

 slightly notched at the antero-internal angle where it is articulated with 

 the next joint. Chelipedes (in the male) well developed, with the palm 

 slightly compressed ; fingers acute, and having between them, when 

 closed, an interspace at the base. Ambulatory legs of moderate length ; 

 the joints subcylindrical, not dilated or compressed; dactyli slightly 

 curved and partially retractile. (Miers). 



Men&tliiiis monoceros, (Latr.) Edw. 



[Pisa monoceros, Latr., Encycl. X. 139.] 



Inachus arabicus, Rtippell, Krab. Roth. Meer., p. 24, pi. v. fig. 4. 



Mensethius monoceros, Milne-Edwards, Hist. Nat. Crust., Vol. I. p. 339. 



Mensethius subserratus, porcellus, and tuber culatus, Adams and White, ' Samarang' 

 Crustacea, pp. 18 and 19, pi. iv. figs. 1 and 2. 



Mensethius angustus, depressus, subserr<itus, tuberculatus, areolatus and inomatus, 

 Dana, U. S. Expl. Exped., Crust. I. pp. 121-125, pi. iv. figs 5a-7g, and pi. v. 

 figs. la-3d. 



Mensethius subserratus, dentatus and depressus, Stimpson, Proc. Ac. Nat. Sci. 

 Philad., 1857, p. 219. 



Menxthius monoceros, Heller, Crust. Roth. Meer., SB. AK. Wien, XLIII. 1861, 

 p. 306. 



Mensethius monoceros, A. Milne-Edwards in Maillard's L'ile Reunion, Annexe F, 

 p. 6 ; and rugosus p. 7, pi. xvii. fig. 2. 



Men^ thius monoceros,, A. Milne-Edwards, Nouvelles Archives du Muse cm 

 IV. 1868, p. 70, and VIII. 1872, pp. 252 and 253 (ubi. synon.) 



43 



