228 
middle of the inner marginal cell;  poststigmatal cross vein 
slightly oblique and rather short, trapezoidal cell moderately elon- 
gate. Prefurca of normal length. Petiole of second posterior 
cell short, rarely exceeding, seldom equaling half the length of the 
discal cell, in one instance (No. 1697) barely one third its length ; 
fifth posterior cell much broader at base than at margin. Discal 
cell fairly large, elongate, arcuate, more than twice as long as 
broad ; it varies in one specimen which seems to belong here (No. 
8944), in being straighter and exceptionally slender, being fully 
three times as long as broad. Sixth longitudinal vein moderately 
near the fifth, but slightly variable, usually nearer than in 7. 
rigens, but occasionally as distant; seventh longitudinal vein 
nearly or very nearly half as long as the wing. Legs slender, the 
femora not greatly stouter than the tibiz and considerably more 
than half as long as the wings, the tibiz distinctly longer than the 
femora, except the middle pair, which is subequal to them; the 
tarsi subequal and fully half as long again as the tibiz. Abdo- 
men pale beneath, above light colored with a rather narrow dark 
median stripe and a pair of similar but generally more conspicu- 
ous lateral stripes, nearer the lateral margins than the middle line, 
unless the abdomen is inflated, as when heavy with eggs, when they 
may recede farther from the margin, as seen from above. 
Length of wings, 16-20.5 mm.; of legs in one specimen, No. 
13685, in which all the legs are perfectly preserved and the wing 
measures 17 mm. long, as follows: fore femora, to mm. ; tibiz, 12 
mm. ; tarsi, 18.5 mm. ; mid femora, 11.5 mm. ; tibice, rr mm. ; tarsi, 
18.5 mm. ; hind femora, 11 mm. ; tibiz, 13.5 mm. ; tarsi, 19.5 mm. 
Florissant, Colorado. Fifty-one specimens, of which ten are ¥, 
the remainder 9 or indeterminate ; Nos. 92, 775, 883 and 1692, 
1617, 1607 and 7732, 2161, 2780, 3267, 32685, 4435, 4618, 5545. 
5595, 6060, 7220, 7721, 8185, 8210, $390, 8538 and 11676, 
8821, 8858, 8944, 9040, 9261, 9857, 10386, 10634, 11137, 
M324, TL3eo, T1220, LOOT, Tree, i S4n 12142, T2705, 
13273, 13280 and 13296, 13281, 13685, 13694, 13724, 139985, 
14004, 14995, 16312 from my collection; also Nos. 1481, 1502 
U. S. Geological Survey ; No. 16420 collected by R. Thaxter ; 
and 1.750 from the Princeton collection. 
