222 A. Alcock — Carcinological Fauna of India. [No. 2, 



outer margin, near the base. Merus of the external maxillipeds as 

 broad as the ischium, and with the antero- external angle produced. 



Chelipeds slender ; ambulatory legs very long and slender. Ab- 

 domen of the male consisting of seven distinct segments. 



Chorilibinia andamanica, n. sp. Plate V. figs. 2, 2a. 



Distinguished from Chorilibinia gracilipes, Miers (Ann. Mag. Nat. 

 Hist. Vol. IV. 1879, p. 7, pi. iv. fig. 4), (1) by the much less divergent 

 rostral spines ; (2) by the pair of great spines — one pointing forwards, 

 the other backwards — ou the cardiac region ; (3) by the much slenderer 

 chelipeds. 



Carapace broadly subpyriform, with (1) a median line of tubercles 

 and spines increasing in size from before backwards, four of the spines — 

 namely one on the after limit of the gastric region, two on the cardiac 

 region, and one near the posterior border — being conspicuously large ; 

 and with (2) on either side a supra -marginal line of spines as follows — 

 a tooth at the angle of the buccal frame, a large hepatic spine pointing 

 downwards, and four branchial spines, the last of which directed ob- 

 liquely backwards is much the largest. Besides these large spines there 

 are numerous, symmetrically disposed, sharp granules. The rostrum, 

 which measured from the anterior border of the orbit is about one-third 

 the length of the carapace proper, ends in two very slightly divergent 

 spines. 



The eyes are short and thick ; and the orbit is formed by a moder- 

 ately prominent supra- ocular eave separated by a narrow interval from 

 abroad isolated post-ocular pocket. 



The basal antennal joint is moderately broad, and bears two teeth, 

 one at the antero-lateral angle, the other at the base — the latter inclin- 

 ing towards the post-ocular pocket. 



The external maxillipeds completely close the buccal frame, the 

 merus being as broad as the ischium. 



The chelipeds are not stouter than the legs, and are but little longer 

 than the carapace (rostrum included) : the next pair of legs are con- 

 siderably more than three times, and the third pair are about three 

 times, this length ; while the 4th and 5th pairs are very short. 



The abdominal segments from the third to the sixth inclusive, are 

 coalescent. 



The sternum between the chelipeds carries a pair of very strong 

 sharp teeth. 



hoc Andamans. 



