Chilopods of the Genus Mecistocephalus. 333 



This is a strongly marked species, readily recognizable by 

 the bluntly rounded distal joint of the palpus of the second 

 maxillae, the form of the labrum, slender claw of the pre- 

 hensors, with absence of tooth from third joint of latter, etc. 



Mecistocephalus apator, sp. n. 

 (PI. XII. figs. 1-6.) 



Head and prehensors blackish. Body fulvous, orange in 

 anterior region. 



Head differing considerably in form from that of monti- 

 colens, which the species resembles, being anteriorly truncate, 

 more gradually narrowed caudad. Posterior margin trun- 

 cate. Head 1'85 times longer than wide. 



The setae of the clypeal region are similar in number and 

 position to those of monticolens, as these are shown in 

 PI. XII. fig. 8. The sublateral spurs are stouter and less 

 bent mesad. 



Labrum somewhat similar in general form to that of the 

 Javan monticolens ; but the exposed part of the median piece 

 has the sides straight or concave instead of convex, and the 

 free margins of the lateral pieces round in cephalad at mesal 

 ends instead of projecting in tooth-like angles (PI. XII. 

 fig. 2; of. PI. XII. fig. 9> 



Mandible with a total of seven lamelke. Of these the 

 first has six stouter teeth (I'l. XII. fig. 4). A median 

 lamella has twelve long teeth, these subuniform in length. 



The aieolated region of the coxosternum of the second 

 maxilke large, the median band broad ; but in this species 

 the non-areolated region on each side extends caudad of the 

 segmental pores. Kctal angles of coxae of first maxillae 

 moderately produced forwards (PI. XII. fig. 3). 



The teeth of the prosternum are small though distinct 

 and larger than in monticolens. The two normal teeth of 

 femuroid present. Of these the more proximal one is low, 

 broad, and rounded ; the distal one is longer and is distally 

 subtruncate. The next two joints also armed, the tooth of 

 the second one the larger. No distinct tooth at base of claw 

 above the basal angulation (PI. XII. fig. 5). 



Sternal impressions simple longitudinal furrows, with no 

 distinct furcation. 



Sternite of pregenital segment trapeziform, strongly 

 narrowed caudad. Coxopleural pores of moderate size, well 

 separated, about twenty-five on each side. 



Pairs of legs, 49. 



