1895.] A. Alcock — Carcinological Fauna of India. 177 



having its lower edge, and the fingers their outside edges, sharply 

 cristate : 



(5) the legs of the second, not of the third, trunk-segment are the 

 longest, and considerably so. 



Length of carapace 11 millim. Breadth of carapace 9"5 millim. 

 Length of legs of 2nd trunk-segment 47 millim., of 3rd trunk-segment 

 40 millim. 



Two egg-laden females from the Andaman Sea, 271 fathoms. 



The eggs, as in the preceding species, are large and few in number. 



The above species represent an Achseus modified for life at a con- 

 siderable depth. The branchial chambers, as is very commonly the case 

 in deep-sea Malacostraca, are greatly inflated : the eyes have degene- 

 rated, and the antennae — no doubt in compensation — have become 

 remarkably lengthened : while the auditory tubercles also, it may be 

 mentioned, are large and prominent. 



Grtpach^us, n. gen. 



Intermediate between Achseus and Echinoplax. 



Carapace triangular, spiny, separated from the frontal region by a 

 post-ocular "neck." Rostrum spiny : composed of two short divergent 

 spfhelets, with a strong median deflexed (interantennulary) spine, not 

 visible from above. Eyes laterally projecting, movable, but not siiffi- 

 ciently retractile to be ever concealed. Small supra-ocular and post- 

 ocular spines are present as part of the general spinature. Antennae 

 dorsally exposed from the basal joint of the peduncle, which joint is long 

 slender cylindrical and spiny. External maxillipeds with the merus 

 elongate, much narrower than the ischium, and not much broader than 

 the carpopodite. Legs hairy and spiniferous. Abdomen six-jointed in $ . 



Grypachseus hyalinus (Alcock & Anderson). Plate III. figs. 4, 4a. 

 Achseus hyalinus, Alcock & Anderson, J. A. S. B., Pt. ii. 1894, p. 205. 



Carapace sub-triangular, thin, vitreous, spiny especially in its an- 

 terior half : the regions well delimited, and the post-ocular portion con- 

 stricted to form a "neck." The rostrum, as seen from above, ends in 

 two short spines, each of which has a spine at its base ; but from in front 

 or from below it shows a strong vertically deflexed (interantennulary) 

 spine. 



The eyes are large ; and the long eye-stalks, which bear two tuber- 

 cles on their front surface, are movable backwards, and are exposed from 



