12 Major A. Alcock an d Capt. A. R. S. Anderson on 



but not distinctly notched in the middle, more than a third 

 the greatest breadth of the carapace ; its free edge is turned 

 vertically downwards to form a narrow concave facet with 

 raised margins. 



The antero- lateral borders are not much more than half 

 the length of the postero-lateral ; they are thin and sharp 

 and are cut into three teeth, of which the first is broad and 

 somewhat emarginate, and the other two are acute. On the 

 postero-lateral borders, just behind the junction with the 

 antero-lateral, is a denticle. 



The eyes are small but well-formed, and are freely movable. 

 The orbits conceal the retracted eyes to dorsal view ; their 

 upper margin is fissured near the middle and the lower 

 margin is slightly excavated just below the outer angle; the 

 inner angle of the lower margin is not prominent, though 

 dentiform. 



The antennules fold transversely and their fossae are 

 freely open to their respective orbits. 



The basal antennal joint is short and slender ; the next 

 joint reaches the front; the flagellum, which arises in the 

 orbital hiatus, is about twice the length of the orbit. 



The outer maxillipeds completely close the buccal cavern. 



The chelipeds in the female (male unknown) are unequal, 

 the large one being not quite twice as long as the carapace ; 

 their surface, under the lens, is finely frosted ; the inner 

 angle of the wrist is strongly pronounced and is capped by a 

 pair of acute teeth. 



Legs moderately stout, unarmed, smooth, almost hairless ; 

 the third pair, which are somewhat the longest, are about 

 two and a half times the length of the carapace. The 

 dactyli are compressed-styliform. 



Colours in spirit French-grey, fingers much darker grey. 



A single female specimen, from off the Travancore coast, 

 430 fathoms, has the carapace 13 millim. long and 16 millim. 

 broad. 



This species is closely related to Pilumnoplax heterochir 

 (Studer), Miers, but is distinguished from it by the entire 

 and more prominent front, by the absence of transverse 

 markings on the carapace, by the longer legs, and by the 

 smoothness of the chelipeds and legs. 



From Pilumnoplax ahyssicola, Miers, which it also closely 

 resembles, it is distinguished by the smooth carapace (to the 

 naked eye), by the turned-down milled edge of the front, by 

 the spinule on the postero-lateral border, by the fissured 

 upper margin of the orbit, and by the double spine of the 

 inner angle of the wrist. 



