102 DIPTERA OF NORTH AMERICA. 



with the spots on the costa. First longitudinal vein beset with 

 bristles, the others naked. 



Hal. Pennsylvania. (Osten-Sacken, on Vernonia, in August.) 



Note. The first of the bands on the wings terminates posteriorly in a 

 faint brown line, running along the discal cell and parallel to the longi- 

 tudinal veins ; the second and third bands being more or less coalescent, 

 the space between the second and the tip of the wing may be described as 

 brown, with five round, hyaline spots (one between the costa and the 

 second longitudinal vein; the second, just below the first, between the 

 latter and the next vein ; the third between the same veins, but nearer to 

 the tip of the wing ; the fourth on the fourth longitudinal vein, just behind 

 the posterior transverse vein ; the fifth and largest at the tip of the wing, 

 between the third and fourth longitudinal veins) ; second posterior cell 

 hyaline, except a margin along the veins, which is clouded. The brown is 

 more or less intense in different specimens, and hence the hyaline spots, 

 especially the posterior ones, are sometimes less apparent. 0. S. 



