132 



NORTH AMERICAN DIPTERA 



6. Third vein ending well beyond the middle of the wing (9). 



Reichertella Enderlein 

 Tliird vein ending before or at the middle of the wing (1, 2, 3, 11). 



Rhegmoelema Enderlein 



7. Third vein ending at or near the middle of the wing (7). 



Aldrovandiella Enderlein 

 Third vein ending at the apical fourth of the wing (6, 8). 



Psectrosciara Kieffer 



Scatposidse II. — 7, Aldrovandiella; S, Psectrosciara; 9, Reichertella uncinata ; 10, Swam- 

 merdamella brevicornis; 11, Rhegmoelema aterrima ; 12, Scatopse notata. (All fitrures after 

 Melander. ) 



