482 



NORTH AMERICAN DIPTERA 



5r R' /?.., 



Anisopus 



(Anisopodida) 



ff Thereva 



( There vidse) 



Pantarbes 



(Bombyliidse) 



Conops 



(Conopidae) 



Scenopinus 



(Scenopinidae) 



Rhamphomyia 



(Empidse) 



/»/, + Ck. 



THE VEINS AND CELLS, COMSTOCK-NEEDHAM SYSTEM 



