HELOMYZIDAE SCTOMYZIDAE. 37 



FAM. XXXIX. HELOMYZIDAE. 



Charact. Neuration of the wings complete; costa bristly; first longitudi- 

 nal vein not abbreviated, but bare ; the auxiliary vein is often 

 rather approximated to it. Front bristly on its upper half only ; a 

 stout bristle at each side of the anterior border of the mouth. All 

 the tibiae with spurs and outwards before their tips with a more or 

 less developed erect bristle. 



The close relation of the Helomyzidse to the Cordyluridse in- 

 duces me to assign them a place here, although the consideration 

 of the smaller size of their two posterior basal cells would remove 

 them to a more distant place, in the neighborhood of the Geomy- 

 zidse and Heteroneuridse. In fact both families are related to 

 the Helomyzidse; but they differ from them by their having the 

 first longitudinal vein abbreviated and the auxiliary vein lying 

 close by it, and besides the Heteroneuridse have the peculiarity of 

 the costa of the wings being without bristles. 



The known X. A. species belong to the genera HELOMYZA and 

 SCHOZNOMYZA. Some of them are likewise identical with European 

 species. 



FAM. XL. SCIOMYZIDAE. 



Charact. Neuration of the wings complete ; two posterior basal cells of 

 rather considerable size ; auxiliary vein well separated from the 

 first longitudinal vein. On the lateral border of the front before the 

 vertical bristles there are two bristles, one behind the other ; face 

 proportionately long without distinct furrows for the antennas ; bor- 

 der of the mouth sharp, without vibrissse. Middle tibiae with a 

 greater number of bristles at the tip ; all the tibiae on the outside 

 before the tip with a small upright bristle. 



I know N. A. species that belong to the genera SEPEDON, TETA- 

 NOCERA, and SCIOMYZA. Some of them are most nearly related to 

 European species, others seem altogether identical with them. If 

 we place, and we may well justify our doing so, the genus DRYO- 

 MYZA among the Sciom.yzidse, it must also be named as a genus 

 represented in N. A. ; one of the two species of this genus occur- 

 ring there does not seem to differ from the European Dryomyza 

 anilis Fall. The genus ACTORA Meig., which agrees with the 

 Sciomyzidse in many characters, may be referred to them without 

 any great difficulty; but on account of its deviation in the struc- 



