Myriapoaa of West Africa. '31 



4. Spirostreptus tripartitiis, sp. n. 



Plates II and III, figs. 17-22. 



Body cylindrical, widest about one-fourth of the length from the posterior 

 end, gradually narrowed anteriorly to about the eleventh segment, in front 

 slightly larger. 



Covered portion of epicraniura with moderately pronounced longitudinal 

 striations. 



Vertex with a broad and deep sulcus, rugulose to the transverse intra-ocular 

 suture; the two sutures meeting in a slight depression. 



Clypeus faintly and distantly rugulose ; near the lateral margins on each 

 side a flattened, or even excavate area; upper row of four irregular, large, 

 shallow punctations ; lower row of seven or eight punctations on each side of, 

 but none above, the emargination. None of the punctations are furnished 

 with hairs, but each has a small rounded protuberance at the bottom. 



Labruni with a deep emargination ; labral teeth very small and blunt and 

 distant from each other, above them a rather deep groove. 



Eyes shaped like half the loop of a lemniscate, arranged ll-f-l'^ + ^+'^or 

 8 -f- 6 -|- 5 -(- 2 ^ 50 or 51 ; distant from each other by about the transverse 

 diameter of an eye. 



Antennae with the second joint longest, the others gradually decreasing in 

 length, the seventh very short ; length 10 mm., diameter of joints about 1 mm. 

 Mandibulary stipe with the exposed surface nearly plane, oblong, with a 

 raised margin along the lower edge. 



Masticatory plate triangular, about twice as long as broad, with a raised 

 edge ; upper portion a deep groove, the exterior edge of which does not attain 

 to the plane of the larger triangular portion, and is without spines. 



Mandibulary tooth triangular, obtuse at point, about twice as long as broad. 

 Dentate lamella with five blunt teeth. 



Pectinate lamellse of eleven complete rows of blunt spines. 

 Hypostoma with longitudinal striations on the inferior surface of the broad 

 ends ; anterior margin medianly produced, otherwise nearly straight. 



Mentum tripartite, the median piece oval, about half as long as the lateral 

 pieces, and nearly equal to them in width ; lateral pieces trapezoidal, the 

 posterior interior corner produced. 



Promentum with posterior corners produced ; anterior margin but little con- 

 vex outwardly ; anterior third beset with numerous bristles. 



Stipe with four or five large bi'istles on the anterior edge, and a fringe of 

 tliem along the anterior two-thirds of the lateral edges ; portion bordering on 

 the promentum also beset with bristles ; a stout, blunt, dark-brown spine is 

 located near the anterior-interior corner. 



Lingual laminse beset with bristles on the posterior half, and three large 

 ones toward the anterior end. 



First segment nearly smooth, slightly rugulose on the sides ; anterior lateral 

 angle considerably produced, rounded, the lateral edge straight, directed 

 slightly upward posteriorly, posterior corner very obtuse ; four complete stria- 

 tions, sometimes branched, or with one or two short striae. 



