1900.] A. Alcock — Carcinological Fauna of India. 319 



more massive and but little shorter than the legs : palm short and rather 

 deep, with the lower border sharply carinate. 



Legs smooth, unarmed, with a very few scattered lank hairs: 

 dactyl i styliform. 



The abdomen in both sexes consists of 7 separate segments and does 

 not nearly conceal the sternum between the last pair of legs. 



Distribution : Indo-Pacific, from Fiji to the Persian Gulf. 



Key to the Indian species of Notonyx. 

 I. Carapace, length about three-fourths the breadth : merus 



of external maxillipeds about as long as the ischium ... N. nitidus. 

 II. Carapace, length about five-sixths the breadth : merus of 



external maxillipeds mnch shorter than the ischium ... N. vitreus. 



20. Notonyx nitidus, A. M. Edw. . 

 Notonyx nitidus, A. Milne Edwards, Nouv. Archiv. du Mus. IX, 1873, p. 269, 

 pi. xii. fig. 3 : Miers, Challenger Brachyura, p. 236. 



Carapace, length a little more than three-fourths the greatest 

 breadth. Front between a third and two-fifths the breadth of the 

 carapace. Orbits elongate. Merus of the external maxillipeds as long 

 as the ischium. 



A small denticle near the far end of the upper border of the arm : 

 inner angle of wrist pronounced, but not acute. 



Legs with some scattered hairs along the edges, the 3rd pair, 

 which are slightly the longest, are about 2J times the length of the 

 carapace and nearly half again as long as the chelipeds. 



In the Indian Museum is a single specimen from the Persian Gulf : 

 its carapace is 8*5 millim. long and 11 millim. broad. 



21. Notonyx vitreus, n. sp. 



Carapace, length about five-sixths the greatest breadth, rather 

 tumid. Front nearly half the breadth of the carapace. Merus of the 

 external maxillipeds shorter than the ischium. 



No denticle on the arm : inner angle of wrist blunt. Legs with 

 hardly any hairs, otherwise resembling those of N. nitidus. 



In the Indian Museum is a single specimen from the Andaman 

 Sea, 53 fathoms : its carapace is 5 millim. long and 6 millim. broad. 



Ceratoplax, Stimpson. 



Ceratoplax, Stimpson, Proc. Ac. Nat. Sci. Philad. 1858, p. 96 : Miers, Challenger 

 Brachyura, p. 233. 



Carapace deep, snbquadrilateral with the antero-lateral angles 

 rounded off, a good deal broader than long, the regions very indistinctly 

 J. ii. 42 



