288 DIPTERA OF NORTH AMERICA. [PART IV. 



2. R. flaveola, n. sp. "J, and 9- — Flava tota ; alis immaculatis 

 cellula discoidali iustructis. 



Entirely yellow ; wings immaculate, with a discal cell. Long. corp. 0.2. 



The whole body, including the feet, is of a pale yellow color ; 

 the thorax above, as well as the pleurce, have a slight hoary bloom ; 

 the wings are hyaline, with pale bi'own veins, except the costa, 

 which is yellowish ; the stigma is elongated, colorless ; the de- 

 tails of the venation have been given above, in the generic 

 character. The first tarsal joint (in the female specimen) is 

 about equal in length to the tibia ; the four following joints, 

 taken together, are rather more than half the length of the first 

 (the feet of the male specimen are broken). 



I possess a male, taken by me in Maryland ; a female, taken by 

 Mr. Scudder, on Mt. Greylock, Mass., is much paler in coloring, 

 almost whitish, but agrees in all the other characters. 



