54 Families and Genera of 



Antennae with a dorsal or subdorsal arista. .... 4 

 2. Face with a median ridge, without ^-shaped grooves. 



^'Tropidoma'ia Will. 



Face with a well-marked _;^-shaped groove 3 



8. Femora and tibite not thickened or dilated, or, if so, the thicken- 

 ing regular; small cross-vein of the wings nearly opposite the 

 tip of the auxiliary vein, and near the middle of the discal 



cell. CoNops 



Femora irregularly thickened toward the base, the tibiae with 

 irregular outlines ; small cross- vein of wings near the outer 

 third of discal cell Physocephala 



4. Proboscis directed forward, not bent near the middle. Zodion 

 Proboscis bent near the middle, the distal part folding back. 5 



5. Vertex with bristles ; tibia? spurred ; face carinate, not grooved ; 



ovipositor of female very long. . . . Stylogaster 

 Vertex and tibiae without bristles ; face with ^-shaped groove. 6 

 (3. Anal cell short ; ovipositor elongate and folded beneath the ab- 

 domen Dalmannia 



Anal cell elongate, acute. 7 



7 Cheeks not as broad as the vertical diameter of the eye. 



Oncomyia 

 Cheeks as broad or broader than the vertical diameter of the eye . 



Myopa 



CoNOPS Linne, Fauna Suecica, p. 1797, 1761. 



Physocephala Schiner, Wien. Ent. Monatschr. V, 18(51. 



Zodion Latreille, Precis etc. 179(3. 



Oncomyia Robineau Desvoidy, Dipt, des Env. de Paris, Myopaires, 



59, 1853. 

 Myopa Fabricius, Syst. Entom. 798, 1775. 



Dalmannia Robineau Desvoidy, Essai sur les Myodaires, 248, 1830. 

 Stylogaster Macquart, Hist. Nat. des Dipt. II, 38, 1835. 



[For description of species, see Williston, Trans. Connecticut 

 Acad. VI, 377.] 



PIPUNCULID.E. 



Small, thinly pilose or nearly bare species. Head nearly spheri- 

 cal, broader than the thorax, composed chiefly of the very large 

 eyes. Eyes in the male contiguous, front in the female narrow. 



