1895. PROCEEDINGS OF THE NATIONAL MUSEUM. 389 



The following table contains all tlie genera of Empida? at present 

 known to occnr in North America: 



ANALYTICAL KEY TO THE NOKTH AMEHICAN GENERA OF EMPID.E. 



1. Third longitudinal vein forked , 2 



Third longitudinal vein simple, not forked 16 



2. Discal lell present, eoin]ilete 4 



Discjil eell united with one of the other eells 3 



3. With only two veins isstiiug from the discal cell, the anterior one forked 



Hemerodromia (p. liitl). 

 With three veins issuing from the discal cell, the anterior one simple, not 



forked Neoplasia (p. 392). 



4 . Three veins issue from apex of discal cell 5. 



Two veins issue from discal cell, fourth vein forked, proboscis perpendicular 



Maniipeza (p. 392). 



5. Anterior branch of the third vein terminates in the costa (except in some 



species of Empis) 6 



Anterior branch of the third vein terminates in the second vein ; anal cell as 

 long as the second basal, the vein at its apex perpendicular to hind 

 margin of the wing Blepliaroprocta. 



6. Proboscis shorter or but slightly longer than heiglit of head 7 



Proboscis much longer than height of head; vein at apex of anal cell nearly 



parallel with the hind margin of the wing 12 



7. Vein closing the anal cell nearly perpendicular to the hind margin of the 



wing 8 



Vein closing the anal cell nearly parallel with the hind margin of the wing. 9 



8. Anterior branch of third vein connected with the second by a cross vein; 



veins 2 and 3 undulating; wings dotted over their entire surface 



Ardoptera, 

 Anterior branch of third vein not connected with the second; veins never 

 undulating; wings not dotted over their entire surface; aluLe well 

 developed Brachijsto7na (p. 393). 



9. .\ntenn;e three jointed 10 



AutenniB one-fifth as long as the head, apparently only two jointed, last 



joint ov<al; style thick, nearly half as long as the antennae; proboscis 

 very short Jformopeza. 



10. Antenna! style nearly twice as long as the third joint ; proboscis soft, much 



shorter than the head 11 



Antennal style scarcely longer or shorter than the third joint; proboscis 



usually rigid Bilara (p. 394). 



11. Alulffi well developed (iloma. 



Alul.-B very small Clhiorrra. 



12. Proboscis directed downward or backward 13 



Proboscis directed forward ; arista of anteunu> very short Ite(tphUa. 



13. Face naked 14 



Face clothed witii bristly hairs Empinwrpha (p. 396). 



14. Hind legs longer than the others, hind femora scarcely or not at all thick- 



ened 15 



Hind legs not longer than the others, hind femora greatly thickened, eyes in 



both sexes widely separated I'achijmeria. 



15. Proboscis not or scarcely longer than height of head Hilara (p. 394). 



Proboscis considerably longer than heigiit of head Empis (p. 397), 



