NINETEENTH ANNUAL MEETING. 125 



16. Longitudinal veins of the wings usually crowded anteriorly, those posteriorly 



often weak; the costal vein does not reach beyond the tip of the wing; an- 

 tennae long or short, with or without a terminal or dorsal arista or style. 



Steatiomyid^ 



Longitudinal veins not crowded anteriorly; the marginal vein encompasses the 



entire wing; third longitudinal vein always furcate, and five posterior cells 



always present; third joint of antennfe never with style or bristle 17 



17. All the tibiae with spurs; third joint of anteunte sometimes divided into sepa- 



rate joints Xylophagid^: 



Front tibiae without spurs 18 



18. Fourth posterior cell of wings closed {Subula) STKAxiOMYiDa;, pf. 



Fourth posterior cell open {Arthrocerince) LEPTiDa:, pt. 



19. Antennae apparently single-jointed, with a long bristle; wings with several stout 



veins anteriorly, and other weaker ones running across the surface uncon- 

 nected by cross-veins; femora flattened; the hind legs long; antennae situated 



near the mouth; small, quick-running, hunchback-like flies Phoeid^ 



Not such flies 20 



20. Empodia developed pulvilliform, that is, three nearly equal, membraneous ap- 



pendages on the under side of the claws 21 



Empodia wanting, rudimentary or linear, not developed like the pulvilli. ... 23 



21. Tegulae very large, inflated; thorax and abdomen inflated; head small, eyes very 



large; neuration varied CyBTiDa; 



Tegulse of moderate size or rudimentary 22 



22. Middle tibia?, at least, with spurs, no bristles on femora or tibiae; third longitu- 



dinal vein furcate; five posterior cells present (four in Agnotomyia); anterior 

 cross-vein always distinct; third joint of the antenna? with a bristle or slen- 

 der style, usually terminal Leptids 



Not such flies 23 



23. Third longitudinal vein of the wing simple, not furcate 32 



Third longitudinal vein furcate, two or more submarginal cells present 24 



24. Arista or style of antennae, when present, always terminal 25 



Arista dorsal, always present 37 



25. Vertex and front distinctly hollowed out transversely between the eyes; eyes of 



male never contiguous; basal cells large; mostly large flies 26 



Front and vertex plane or convex; eyes of male often contiguous 27 



26. Proboscis without fleshy labellas at the tip, the under part forming a horny 



sheath; the posterior branch of the third vein terminates behind the tip of 



the wing; five posterior cells always present; predaceous flies AsiLina: 



Proboscis with fleshy labellje at the tip; neuration complicated, the third vein, 

 at least, curves forward to terminate before the tip of the wing; antennae 

 with a terminal flattened lamella Midaids: 



27. Five posterior cells in the wing; basal cells large 30 



Never more than four posterior cells in the wing 28 



28. Third antennal joint without bristle or style; three posterior cells; first pos- 



terior cell narrowed or closed, the fourth longitudinal vein terminating at or 

 before the tip of the wing ScENOPiNioa; 



