50 A 



REVISION OF THE NEARCTIC SCIOMYZIDAE 



lunule not conspicuously protruding, although distinctly visible. 

 The middle femora have one or more median anterior bristles; 

 fore and hind femora have flexor and extensor bristles, and the 

 fifth abdominal segment has well developed marginal bristles. 

 In the known species the general color is honey or wax yellow, 

 with at most mesonotal and pleural stripes of brown, and the 

 apices of tarsi darker; arista l)lack, pubescent or plumose. The 

 wings are infuscated only along the costa and on the posterior 

 cross-vein, and, in two of the more aberrant species, forming a few 

 transverse bars between the veins; but the wings are never dis- 

 tinctlv reticulated. 



In geiuMal appearance the species resemble those of Dryomyza 

 and allies, or, in antennal structure, some species of Melina. 

 There is, however, no danger of confusion along these lines when 

 note is taken of the absence in this genus of the propleural bristles. 

 The species of Renocera have no femoral or abdominal bristles, 

 but otherwise might he confused as allies of unicolor. 



Key to the Species 



1. Wiiifis marked with narrow bars between veins 2 



Wings immaculate except costal infuscation 3 



2. Marginal cell with distinct fuscous spots valida 



Marginal cell immaculate except a cloud at apex, rarely with otlier faint 



spots ..Clara 



3. I'rons with but one frontal bristle; third antennal joint broad apically. 



brevis 

 Two frontals present; third antennal joint tapering apically 4 



4. Second antennal joint not as long as broad; small species (5 mm.)- 



unicolor 



Second antennal joint as long or longer than broad; larger species (6 to 



20 mm.) 5 



5. Apices of hind femora distinctly brcjwn; fifth ventral segment of male not 



visible 6 



Ai)ic('s of femora not brown; fifth ventral easily visible 7 



(i. Lalcral shining frontal stripe not attaining anterior margin of frons. 



ferruginea 



Lah'ral shining stripes, attaining margin, which is also shining. . .silvatica 



7. Middle femora with di.stinct, stout bristle near apices on posterior side; 



liind cross-vein generally biangulate or strongly bisinuatc vicina 



Mil Idle femora without such bristle elata 



The sy)ecies treated here seem to divide into the following, 

 iiiorc or less well-marked groups. 



