702 PBOCEEDINGS OF THE NATIONAL MUSEUM. vol.xxi. 



half the preceding; the carina} small and dentiform, not projecting as 

 far as those of segment 18. 



Last segment short, broadly triangular, rounded and subtruncate at 

 apex, dorsally witli several transverse furrows, the deei)est of which 

 separates the apically thickened and somewhat upturned part of the 

 segment from the basal. 



Anal valves scarcely convex, rugulose; margins distinct, prominent, 

 shining, subconipressed. 



Preanal scale rugulose, triangular; the apex pointed ; setiferous tuber- 

 cles located close to the apex, large and prominent ventrad, not pro- 

 jecting caudad beyond the apex. 



Sterna si)arsely hirsute with long hairs; the bases of the legs con- 

 nected, except at the middle line, hy distinct, sharp, transverse ridges. 



Process of the sternum of the sixth segment hirsute distad with 

 very long hairs; apically thicliened andj)oiuted; broader below, espe- 

 cially from slight shoulders about the middle. 



Process of sternum of fifteenth segment, as in Astrodesmus stellifer, 

 broadly subtriangular and rounded, medianly grooved below; the edges 

 of this process continuous with the transverse ridges found on other 

 sterna. 



Legs of male hirsute with long bristles, especially on the distal joints 

 of the anterior ; tubercles wanting. 



Anterior male legs with fleshy apical sole small, present on the first 

 six pairs. 



Copulatory legs with the basal part of the second joint much longer 

 proportionally than in Astrodesmus; viewed from below, they show a 

 long spine, which in Astrodesmus appears only as a small denticule; 

 the slender tiagella rise from the posterior side of the large knot-like 

 thickening at the base of a posteriorly directed tubercle; the flagellum 

 curves strongly dorsad, then cephalad, mesad, and finally again dorsad, 

 and ends in a small mesially directed hook which lies on the base of 

 the large spine referred to above; thus each flagellum is coiled upon 

 its own leg and does not cross to the other side and become entangled 

 with its fellow. 



Color of dried specimen pale alutaceous, the legs showing a tinge of 

 reddish, which, according to Peters's figure, was shared by the whole 

 body. 



Length, 55 mm.; width, 11.4 mm. 



Locality/. — Rios de Sena, near the Zambesi. Dr. Peters collected 

 three male specimens, and at first considered them a variety of mos- 

 sambicus. That from which the above description was drawn is No. 

 199 of the Berlin Museum. 



This species is strikingly distinct from other Gomphodesmidje in the 

 more horizontally directed carina?, which cause the dorsum to appear 

 unusually flat, and by the greater posterior production of the cariuie. 

 The form of the copulatory legs is also quite distinct from that of mos- 



