36 U. S. NATIONAL MUSEUM BULLETIN 216 



13. Sublateral longitudinal carina of third tergite strong, extending 0.5 to 0.8 



the length of the tergite; front spur of middle tibia about 0.50 as long as 

 hind spur; hind coxa mostly or entirely black, rarely entirely fulvous. 



2. costatus (Davis) 



Sublateral longitudinal carina of third tergite weak, extending only about 



0.25 the length of the tergite; front spur of middle tibia about 0.58 as long 



as hind spur; hind coxa fulvous 3. flavifrons (Ashmead) 



14. Hind tibia uniformly fulvous or ferruginous, not at all paler at base; face and 



clypeus of female fulvous, in profile strongly convex below 15 



Hind tibia pale yellowish on its basal 0.2 ±, the rest darker 16 



15. Flagellum of male with 29 to 33 segments, of female with 24 to 26 segments; 



median segments of female flagellum about 1.0 as long as wide; hind tarsus 

 of male ferruginous or fuscoferruginous . . . 11. integer, new species 

 Flagellum of male with 26 to 27 segments, of female with 19 to 21 segments; 

 median segments of female flagellum about 0.85 as long as wide; hind tarsus 

 of male stramineous 12. fusus, new species 



16. Face and clypeus black, the face with a yellow margin on its interantennal 



projection (fig. 179, d) 13. aquilus, new species 



Face and clypeus mostly or entirely yellow or fulvous 17 



17. Front wing 4.2 to 5.2 mm. long 18 



Front wing 2.6 to 4.0 mm. long 19 



18. Wrinkling of metapleurum covering about 70 percent of its area (fig. 181, a); 



yellow of lower lateral corner of frons reaching just to center of eye emargi- 

 nation; eye of male with short, sparse hairs ... 9. ejectus, new species 

 Wrinkling of metapleurum covering about 30 percent of its area (fig. 181,b), 

 yellow of lower lateral corner of frons reaching above center of eye emargi- 

 nation; eye of male apparently bare 10. walteyi, new species 



19. Hind coxa fulvous, somewhat darker basally 20 



Hind coxa black or blackish, often somewhat ferruginous apically .... 21 



20. Lower lateral corner of frons of both sexes with a conspicuous yellow (male) 



or fulvous (female) area that reaches dorsad beyond center of eye emargina- 



tion; front wing 3.1 to 3.3 mm. long 15. marlatti (Ashmead) 



Lower lateral corner of frons of female (male unknown) with a faint ferrugi- 

 nous area that does not reach center of eye emargination; front wing 2.6 

 to 2.8 mm. long 16. bradleyi, new species 



21. Wrinkles of metapleurum extending forward of its middle (fig. 181,f); eye 



inconspicuously hairy, or bare; lower lateral corner of frons yellow. 



14. sparsus, new species 

 Wrinkles of metapleurum restricted to its hind 0.4 (fig. 182,a); eye densely 

 and conspicuously hairy, lower lateral corner of frons blackish. 



17. ciliosus, new species 



I. TEXANUS GROUP 



Head of moderate width; body of moderate proportions; eye with 

 very short sparse hairs or bare; mesopleurum often with fine longi- 

 tudinal or oblique wrinkles near middle coxa; metapleurum without a 

 vertical slot in its hind end, bare of hairs except for a few in its ex- 

 treme upper front corner and a group of hairs of variable number in 

 its upper posterior part, in the hairy area with small punctures, 

 elsewhere polished and with wrinkling of variable extent, the wrin- 

 kling strongest next to hind coxa (figs. 180, a-h) ; median and sublateral 



