FLIES OF THE TRIBE LESKIINI—JAMES 93 
by a few setulae, rarely by several short bristles; facials otherwise 
bare. Eyes bare or practically so. First segment of antenna short, 
erect; second moderately long; third 2 to 3.5 times as long as second ; 
arista with both basal segments short, the third slender, somewhat 
thickened basally, with moderately dense short hair to tip. Posto- 
cellar bristles small, one-fourth to one-third length of inner verticals, 
the latter strong; usually two, sometimes three or four, gnathoorbitals. 
Transverse suture distinct, crossing mesonotum at or somewhat 
before middle. Presutural acrosticals present or absent; one post- 
sutural (prescutellar) acrostical; two or three presutural dorsocen- 
trals; three postsutural dorsocentrals; no posthumeral; usually one 
preintraalar, the hind one, when present, being weak; three (rarely 
two) postintraalars; one, sometimes two, presupraalars; three post- 
supraalars, the middle one especially strong; intrapostalar absent or 
extremely weak; two postalars, the hind one especially strong; nor- 
mally three sternopleurals. Wing 0.40 to 0.45 as wide as long; cell R; 
narrowly open or rarely short-petiolate, ending not more than length 
of cross vein r-m from wing tip; vein R, with setulae extending to its 
apex, or at most with one or two apical setulae missing; vein R; setulose 
approximately to cross vein r-m, the setulae ending sometimes slightly 
before, sometimes slightly beyond that point; stem vein (base of radius, 
or the remigium or Townsend’s terminology) bare; vein R; bowed 
down apically; cubitulus gently rounded and without a stump; apical 
section of Cu, short; cross vein r-m half to three-fifths the distance 
- from r-m to the cubitulus, 
Abdomen short; ovate; first segment with a pair of lateral bristles, 
with or without a pair of median marginals; second segment with one 
or more pairs of laterals; third and fourth each with a marginal row; 
no discals on any segment. Male genitalia small, anal forceps broad 
basally, with a narrowly tapered slender point; both anterior and 
posterior claspers present; aedeagus short and rather slender. 
In coloration the species conform to a fairly uniform pattern. The 
body is either actually predominantly yellow or apparently so as a 
result of the dense pollinosity which obscures the areas of black back- 
ground on the head and thorax. Each half of the mesonotum has two 
longitudinal vittae formed from brownish to black pollen; the inner 
one, located between the dorsocentral and acrostical rows, is narrow, 
from one to three times as wide as the diameter of a trichopore of a 
dorsocentral bristle; it is not interrupted at the suture and may reach 
the anterior margin of the mesonotum; the outer and much broader 
one, located between the dorsocentral and intraalar rows, is distinctly 
separated by pale-pollinose areas from both the anterior and the pos- 
terior margin of the mesonotum, and is broadly interrupted at the 
suture. The abdomen is yellow in background, with black markings. 
