NORTH AMKKICAN DIPTKItA. 105 



pair, anal witli a row of niai-jrinal niacroclinetiu. Le^s black, ftMiioia aiitl tibia' 

 somewhat bristly; pulvilli dirty whitish. Win;rs grayish hyaline, siijihtly pale 

 tawny at extreme base, apical (^ell moderately long petiolate. apical cross-vein, 

 concave, a slijrht fuscous spot at bend of fourth vein; teguhe nearly white, 

 halteres dusky. F^ength of body nearly 7 mm. ; of wiiifi 4..") mm. 



Described tVoiii one s|)eciinen ; Las duces, X. Mex., October 10th. 



\K0TI«A<T0CI-:K.4 d. gen. 

 Grayish and brownish s|)ecies of medium size, with much the facies 

 of Hypertrophocera, but readily distinsfuislied by tlie much smaller, 

 very narrowed, elongate and linear third antennal joint. Belongs 

 in the Tacliininte. Head rather triangular in profile, the facial pro- 

 tile very long, the oral very short ; front quite prominent, about one- 

 half width of head in 9 . wider before than at vertex, face widened, 

 hardly three-fifths width of head ; frontal bristles in a double row 

 (the outer row being composed mostly of orbital bristles), short and 

 about equal, except vertical bristles which are strong and directed 

 backward, descending in a single row on sides of face as low as lower 

 border of eyes ; three or more orbital bristles in 9 . Face very 

 long and receding, epistoma not prominent ; facial depression rather 

 less than one-half width of face, elongate, a little widened below, 

 rather deep ; facial ridges bare, except a few bristles next vibrissje, a 

 little constricted below; sides of face wide and long, bare outside the 

 frontal bristles; cheeks wide, about one-half eye-hight, hairy behind 

 and bristly on lower border; vibrissa? moderately strong, decussate, 

 inserted about on oral margin. Eyes bare, descending about three- 

 fourths as low as oral margin. Antennse much shorter than face, 

 inserted high, first joint short, second hardly elongate, third about 

 five times as long as second, very narrow, elongate, linear, but some- 

 what widened at base; arista rather long, curved toward tip, bare, 

 thickened whole length, 8-jointed, second joint short. Proboscis short, 

 not much longer than one-half bight of head, somewhat stout, iabella 

 well developed; palpi very slender, nearly filiform, slightly thickened 

 at tip, reaching to tij) of proboscis when latter is bent forward. 

 Thorax as wide as head; scutellum with an apical, non-decussate pair 

 of macrochiette hardly exceeding base of second abdominal segment, 

 a sublateral, and a weaker discal pair. Abdomen wider than thorax, 

 broadly ovate, or nearly round in outline, more or less flattened, 

 first segment not shortened; macrochjeta? marginal and di.scal, at least 

 on last segment. Legs moderately long, a little bristly; claws and 

 pulvilli of $ short. Wings longer than abdomen, broad, with snmll 



TKANS. AM. ENT. SOC. XIX. (14) .MAY, 1892. 



