419 



that spot. Pronotum with two distinct and one indistinct 

 carinae; shoulder keels large. 



$ Light orange yellow. Tegmina hyaline, very light yellow over 

 costal and apical cells, opaquely white with waxy secretion, a small brown 

 spot at fork of cubitus and another near cross vein of first median 

 sector; wings hyaline, veins concolorous, opaquely white with waxy 

 secretion. 



Ventral edge of pygophor straight, ventral surface tumid in middle, 

 lateral edges slightly convex ; anal segment long, narrow, slightly 

 widened at apex which is bilobed, anus near apex; genital styles long, 

 ventral edge with an angular projection near base, beyond which edge 

 is slightly sinuous, apex rounded with a subangular projection on the 

 dorso-apical margin, dorsal margin entire, a carina runs down the outer 

 surface near dorsal margin, on the inner surface in middle there is a 

 spine with a curve and somewhat flattened crook at the apex. 



Length 2.6 mm. ; tegmen 2).y mm. 



1 



Figure 1. Phaciocephalus bipuncfata^ tegmen. 



Hab. Bartica, British Guiana, August, 1901 (Coll. H. S. 

 Parish). Described from one male specimen. Type in coll. 

 Prof. H. Osborn. 



Genus Syxtames Fowler. 



Fowler describes *S'. delicatus from what he states to be 

 males but they are females. The variety chiriquensis appears 

 to me to be specifically distinct from 8. delicatus. 



When tabulating the genera of Derbidae'^ I had only a 

 damaged specimen to examine and I placed the genus in 

 Group I. In the two following species one has the clavus nar- 

 rowly open and the other has it closed, otherwise they are 

 congeneric with ^S'. delicatus. 



S. nigrolineafus sp. nor. 



9 Clavus closed, claval veins joining the suture a little before the 

 apex. Shoulder keels large ; no subantennal process ; medio-frontal carina 

 somewhat obscured towards the apex. 



H. S. P. A. Ent. Bull., Xn, T913. 



