108 C. H. TYLER TOWNSEND. 



longer than abdomen, with very small costal spine; apical cell closed 

 in margin well before tip of wing, or exceptionally very short petio- 

 late, apical cross-vein nearly straight or a little bowed, fourth vein 

 bent at a curve ; hind cross-vein moderately or strikingly sinuate, a 

 little nearer to bend of fourth vein, or nearly in middle. Type, P. 

 neomexicana n. sp. 



Pseudatraetocera neomexicana n. sp. % .—Eyes dark brown, 

 frontal vitta brown, sides of front, face and cheeks silvery white, prffi-genal area 

 brown in some lights; anterior pair of ocellar bristles strongest, directed for- 

 ward ; antennae light reddish yellow, third joint brown, arista light brownish ; 

 proboscis brownish, palpi brownish yellow, with some black bristles on under- 

 side; occiput cinereous, gray-hairy below, fringed with black hairs on orbital 

 margins. Thorax silvery cinereous, with four narrow black vittse not reaching 

 scutellum ; scuteiluni silvery cinereous. Abdomen silvery cinereous, certain 

 portions, especially base of first segment and posterior margins of others, black- 

 ish in some lights; first segment with lateral bristles, second with a lateral 

 macrochseta and a median marginal pair, third with ten or more marginal, and 

 anal with marginal and submarginal macrochsette. Legs bla(^k, femora and 

 tibiae bristly, femora slightly silvery on outer portions; pnlvilli dirty whitish, 

 foot-claws and pulvilli long. Wings grayish hyaline, apical cell closed in mar- 

 gin ; tegulse whitish, halteres yellowish. 



9. — Front wider, two orbital bristles; claws shorter. 



Length of body 5 — 6.5 mm. ; of wing 4.5 —6 mm. 



Described from seven males and one female ( $ gave smallest 

 measurement) ; Las Cruces, N. Mex. Males all taken June 2d, the 

 female September 23d. 



G\ i^NOPROSOPA n. gen. 

 Small blackish species, with thorax and bases of abdominal seg- 

 ments silvery. Belongs in Tachininie. Head more or less triangular 

 in profile, oral profile rather short; front prominent, in S hardly 

 one-third width of head, in 9 very distinctly more than one-thiixl, 

 face nearly same width as front in female wider than front in 

 S ; frontal bristles not descending below base of antennae, vertical 

 bristles longest, and, with next two pairs, directed backward, others 

 usually inward and decussate; two orbital bristles in both sexes. 

 Face receding, epistoma somewhat prominent ; facial depression more 

 than one-third width of face in 9 . about one-half in S , only a little 

 wider below, moderately deep ; facial ridges bare, or with only one 

 or two minute bristles next vibrissa, constricted below ; sides of face 

 moderately wide, wider in 9 than in % , bare ; cheeks fully or nearly 

 one-third eye-hight, bare, hardly any or only very small bristles on 

 lower margin ; vibrissas moderately strong, decussate, inserted on oral 



