434 Mr. R. I. Pocock on new 



Dorsum of posterior segments coriaceous, not granular, 

 upperside of keels granular ; margins of keels lobulate, 

 straight ; pore about a diameter and a half from the edge. 

 Caudal process with its margin less convex than in Andersonii. 



Copulatory organ with the prongs differently curved, the 

 inner being bent more abruptly backwards and the outer less 

 abruptly backwards. 



Measurements in millimetres. — Total length 64 ; width of 

 second segment 8"2, of fifth 10. 



Loc. Pinang {H. N. Ridley). 



Acanthodesmus pei'aJcensis, sp. n. (Fig. 7, p. 431.) 



As large as Andersonii, but differently coloured and more 

 coarsely sculptured. 



Legs and antennse flavous as in that species ; dorsum of 

 keel-bearing portion of segments brown, lateral portions on 

 base of keel noticeably darker, the rest of the keel flavous ; 

 cylindrical area of segments dorsally pale brownish yellow 

 with a median black band. 



Dorsal surface of all the segments, even at the end of the 

 body, very distinctly granular, more so than in Andersonii. 



Copulatory organ with practically the same curvature of 

 prongs as in Andersonii. 



Measurements in millimetres. — S (small). Total length 68 ; 

 width of fifth segment 10. ? . Total length 82 ; width of fifth 

 segment 13. 



Loc. Perak. Specimens presented by J. H. Leech, Esq. 



Acanthodesmus Petersii, sp. n. (Fig. 8.) 



^. — Colour faded, apparently as in perakensis, but the 

 keels without indication of a black basal patch, as much 

 yellow on them as in Andersonii, the cylindrical part with 

 traces of a median dark line. But apart from its colouring, 

 which is of doubtful value, seeing that the specimen is faded, 

 the species certainly differs from both Andersonii Sixxdi perak- 

 ensis in the form of the copulatory foot, the inner prong of 

 which is not bent backwards but inwards, then slightly 

 forwards at the tip. 



Measurements in millimetres. — Total length 72 ; width of 

 fifth segment 10. 



Loc, Malay Peninsula {Ind. Mus.). 



Acanthodesmus lineatus, sp. n. (Fig. 9.) 



^. — Colour black, the edges of the keels very narrowly 

 bordered with pale yellow and a narrow (1 mm. wide) 

 longitudinal dorsal baud extending from the upper surface of 



