1916.] S. Kemp : Notes on Crustacea Decapoda. 365 



rostrum is, however, more definiteh' concave in dorsal view and the 

 anterior tooth of the second lateral carina of the carapace is less 

 acute. The outer margin of the merus of the first legs terminates 

 in a small spine and two similar spines exist between it and the 

 articulation of the carpus: these spines do not exist in the type. 

 The dactylus of the second legs is proportionately shorter than in 

 the female, less than twice the length of the palm. The dorsal 

 carina of the fourth abdominal somite is feebly channelled longitu- 

 dinal h' ; that of the fifth is similar in its anterior half, but poste- 

 riorly it is split into two divergent branches. On either side of the 

 median line in the third, fourth and fifth somites are short but 

 well defined carinae, which are transverse on the third but take a 

 more oblique direction on the two succeeding somites. In the type 

 specimen these lateral carinae are obsolete and the median keel of 

 the fourth somite does not appear to be bifurcated posteriorly. In 

 the pleopods there is a wide difference between the sexes. The 

 endopod of the last four pairs is well developed in the female ; but 

 in the male is exceedingly small in the second, third and fourth 

 pairs and is entirely absent from the fifth. 



In life the male was almost pure white in colour with a black 

 spot in front of the median tooth of the carapace, a pair of similar 

 spots on either side between the first and second lateral carinae 

 and a pair near the posterior margin. There were transverse 

 bars of black pigment on the fourth abdominal somite and on the 

 tail-fan, a black band near the distal end of the subchela and 

 three similar bands on the fourth leg, situated on the ischium 

 merus and propodus. 



^1%^ Port Blair. Andamans. 6 fms. S. Kemp. i ^. S mm. 



Pontophilus candidus, sp. nov. 

 (Plate viii, fig. 3.) 



The rostrum is flat and not channelled longitudinally; its lat- 

 eral margins are curved, convergent from the base to the middle 

 and divergent from the middle onwards. The distal end, seen in 

 dorsal view, is abruptly and squarel}^ truncate. The true apex of 

 the rostrum is sharply deflexed : it is visible only from in front 

 and has a broadly convex margin. 



The carapace is entirely devoid of carinae : its surface, though 

 smooth to the naked eye, is microscopically scabrous. The trans- 

 verse depression usually found behind the rostrum is obsolete. 

 The spinulation shows a remarkable difterence- in the two sexes. 

 In the male there is a sharp spine in the median line a little behind 

 the base of the rostrum, but of this in the female there is no trace. 

 In both sexes there is a sharp hepatic spine, situated about on the 

 same level as the dorsal spine of the male, and below and in 

 advance of it is another conspicuous spine situated behind the 

 branchiostegal angle. In the male there is a short longitudinal 

 groove above the hepatic spine and another beneath it, shallower 



