ART. 9 TWO- WINGED FLIES OF TEIBE MILTOGRAMMINI ALLEN 97 



to Coqiiillett or Aldrich, it becomes evident that folita and darifrons 

 are synon\Tnoiis, but that argent if rons, considered synonymous with 

 polita by the above, is clearly a distinct species. 



Female. — Front at narrowest 0.43 of head width (measurements of 

 four 0.40, 0.42, 0.44, and 0.45, respectively), noticeably flattened ; frontal 

 vitta yellow, with the sides nearly parallel but perceptibly wider at the 

 reclinate orbital than at either end, slightly more than twice width 

 of j^arafrontal at lowest orbitals; five to six moderately strong bristles 

 in frontal row; one reclinate and two proclinate orbital bristles; 

 the orbitals, ocellars and inner verticals slightly larger than the 

 frontal bristles; parafrontals silvery, bare or rarely with a few s])arse 

 hairs; facial ridges with one or two minute bristles just above vi- 

 brissae; face silvery; parafacials bare; in profile, buccal width one- 

 fourth eye height; vibrissae slightly more than half length second 

 antennal joint above front edge of oral margin; antennae extend 

 four-fifths distance from their base to the vibrissae; second joint red; 

 third joint black and three times as long as the second, straight along 

 front edge with blunt point at outer apical angle; arista thickened on 

 basal half; proboscis sHghtly less than head height; palpi yellow, dis- 

 tinctly clavate. Thorax gray ])ollinose over black, with bronze 

 reflections on notum, and with three black vittae of which the median 

 one is narrower than the other two; scutellum with three pairs of 

 marginal bristles of which the extreme lateral jiair is distinctly 

 smaller than the apical, but both are much weaker than the inter- 

 mediate pair. Abdomen shining black, excepting silvery pollinose 

 bases of the last three segments, the pollinose bands less than one- 

 third length of segments, terminating abru]:)tly at the side and not 

 continued ventrally; first segment without bristles, second with one 

 lateral and one median marginal ]'air, third and fourth with marginal 

 rows of about ten, the bristles of third segment as large or slightly 

 larger than those of the fom'th. Wings subhyaline, slightly smoky 

 along the costal margin; last section of fourth vein slightly arcuate 

 and not parallel to the hind cross vein which joins the fourth vein a 

 little less than half the distance from its bend to the small cross vein ; 

 last section of fifth vein one-fourth the length of ])receding section; 

 two small costal spines; third vein with row of small bristles extending 

 more than half way to small cross vein. Legs black; pulvilli less than 

 half length of last tarsal joint; middle tibia with single bristle on outer 

 front side near middle; hind tibia with row of two to four unequal 

 bristles on outside extending to slightly below the middle. 



Male. — Front at narrowest 0.39 of head width (measurements of 

 three 0.36, 0.39, 0.41, respectively); frontal vitta diverging slightly 

 towards vertex, more than three times width of parafrontal at lowest 

 orbitals; third joint of antennae three and one-half times as long a 

 second. A tuft of conspicuous hairs located on ventral side of 

 54292— 26t 7 



