1895. PROCEEDINGS OF THE NATIONAL MUSEUM. 95 



Sternum of segmeut G with two similar processes between the anterior 

 pair of legs 



Stem a of post genital segments of male with a stout, sharp, conical 

 spine at the base of each leg, more i^ronounced on posterior segments 

 and larger between the posterior j^air of legs of each segment. 



Sternum of segment 15 not diflerent from its neighbors. 



Legs of male crassate, hirsute, with long bristles, the joints in order 

 of length 3, 2, 4, 5, C, 1. 



Second legs of male with the coxa' produced ventrad into a rounded- 

 conic, somewhat recurved process; genital opening on the median face 

 of the coxa, at the base of the process. 



Seventh pair of legs with a broadly conic process on the ai)ex of tlie 

 intiated coxa, directed mesocephalad. 



Pregenital legs of male with the distal joint supi)lemented at apex 

 by a cushion-like process as long as the very slender claw. 



Two distal joints of male legs roughened on the ventral face by 

 papilliform tubercles, very large on postgenital legs. 



Male genitalia with a broad basal joint; second joint incurved at 

 base, ungual portion subetpial in length with the other, slender, 

 straight, bifid at apex. 



This genus is remarkable in the number of secondary sexual charac- 

 ters, rivaling Scytonotus in that sort of specialization. Like ^Seyfouotus, 

 it ai)i)ears to be very distinct from the related genera, though in liabit 

 the resemblance to Aulodesmus is very striking. Approximations iu 

 habit between members of widely different families are, however, too 

 numerous among Diplopoda to warrant the inference of affinity except 

 from a combination of the more constant structural characters. To 

 indicate such an agreement for the present genus is not easy, but in 

 spite of the difference in pore formula iu the numerous secondary 

 sexual characters no genus suggests itself as having more in common 

 with the present than Aulodesmus, agreeing as it does in habit, mouth 

 parts, the small basal joint of the male genitalia, and in tlie tubercu- 

 lation and membranous sole of the anterior male legs. 



In this genus the first segmeut is much more rounded laterally than 

 in Aulodesmus, being without an apparent angle; the whole segment is 

 more convex, making the ends more decurved; it is narrower in com- 

 parison with the second segment. It is, furthermore, not subemargi- 

 uate toward the ends, as in Aulodesmus. 



The greater convexity is shared by the entire body, which has the 

 dorsum morearched and the cariuiie more depressed than in Aulodesmus. 



MARPTODESMUS CHANLERI, new species. 

 (PI. IV, tigs. 1-10.) 



A'ertex smooth and shining, sulcus transversely rngulose, not deeply; 

 postautennal depression subvertically i ngulose near the lateral margin. 



Cly[)cus smooth and shining, a sharj), oblicjue de])ressi()n parallel to 

 the lateial margin, halfwav between the margin and the antennal 



