I2 8 NORTH AMERICAN DIPTERA. 



EE. Empodia trifid.* 



9. Antennae composed of twelve joints in l)oth sexes. 



Arnoldia K. 



10. Joints of antennae more numerous in male than in fe- 



male; last abdominal segment not swollen. 



Dryomyia K. 



11. Antennae composed of more than twelve joints; last ab- 



dominal segment swollen <9b • • Dasyneura. 

 HI?. Anterior border of the wings without squamae; claws simple. 

 !•'. Empodia simple. 



12. Palpi with four joints; antennae fonrteen-jointed, verti- 



cillate Schizomyza K. 



13. Palpi four-jointed; antennae fonrteen-jointed, not verti- 



cillate Polystepha. 



14. Palpi three-jointed; costa with squamae. Cystiphora K. 



15. Antennae fonrteen-jointed, not verticillate; palpi with 



less than four joints. . . . Asphondylia. 



FF. Empodia trifid; antennae verticillate. 



16. Palpi with one or two joints. . Rhopalomyia R. 



17. Palpi with three joints. . . Oligotrophus Lat. 



18. Palpi with four joints, long. . . . Janetiella K. 



19. The second vein reaches the tip of the wing, palpi with 



four joints Mayetiola K. 



20. Palpi with four long joints. . . . Mikiola K. 



21. Thorax produced over head. . . Hormomyia. 

 BRH. Thorax not prolonged over the head; antenna; fonrteen-jointed 



in 1>oth sexes; in the male each joint of the flagellnm with two 

 bead-like swellings, giving an appearance of twenty-six joints 

 for the antennae. 

 G. Claws of front tarsi bifid, or curved at right angle and enlarged 

 at extremity; or the einpodinm trifid. 



22. Empodia trifid. ..... Putoniella K.. 



23. Verticils of antennae curved and irregular; larva; zo- 



ophagons Bremia Rond. 



24. Verticils regular; all the claws bifid. Dicrodiplosis K 



25. Verticils regnlar; hind claws not bifid; larvae mycophag- 



ons Mycodiplosis R. 



26. Claws simple, bent at right angles and dilated below 



near extremity. . . . Octodiplosis Giard. 

 i.e.. Claws simple, bent or curved at right angles, but not en- 

 larged; empodia simple. 



27. Three-jointed palpi; scales of wings elongated and nar- 



rowed at base Endaphis K. 



28. Second longitudinal vein terminates before the tip of the 



wing; larvae zoophagous. . Arthrocnodax Rbs. 

 24. Palpi with a single jomt . Monarthropalpus R. 



30. Palpi two-jointed, the first long and attenuated in the 



middle Massalongia K. 



31. Palpi with three joints; second joint of antennae with a 



tooth Acrodiplosis K. 



* I use this expression, not being certain whether or not the trifid 

 character is due to real pnlvilli. Kieffer simply begs the question by 

 the expression 'pelote unique,' 'pelotes trois'. 



