194 Proceedings of the Biological Society of Washington. 



21 — Frontals not diverging, stopping practically at base of antennae 22 



Frontals diverging at least one bristle below base of antennae 23 



22— Cheeks well over one-half eye-length in breadth . . 



Miltoravinia, gen. nov. 



Cheeks less than one-half eye-length in breadth 



Euravinla, gen. nov. 

 23 — First hypopygial tergite entire, the disk with a double im- 

 pression as though scooped out on each side of median 



line in a subtransverse oval Kellymyia, gen. nov. 



First hypopygial tergite incised on median line posteriorly, 

 without discal excavation or impression Zygastropyga, gen. nov. 

 24 — First hypopygial tergite entire, neither incised nor excised . 25 



First hypypygial tergite either incised or excised 30 



25 — Facio-orbital row including coarse strong hairs or weak bris- 

 tles below, contrasted with the hairs in line above them . . 



Spirobolomyia T. 

 Facio-orbital row consisting entirely of short or weak hairs, 



or vestigial 26 



26 — First hypopygial tergite transversely dished like a wide shal- 

 low groove 27 



First hypopygial tergite not dished 28 



27 — Theca immensely broad as well as elongate, nearly as broad 



basally as long; palpi greatly swollen apically 



Gigantotheca, gen, nov. 

 Theca not unusually broad; palpi normal . . Umbelusia, gen. nov. 

 28 — Strong median marginals on segment III; first hypopygial 

 tergite shield-like, broad, with disk directed posteriorly . . 



Peltopyga, gen. nov. 

 Median marginals absent or vestigial on segment III ... . 29 



29— Parafacialia about or nearly as wide as clypeus ; first hypo- 

 pygial tergite strongly crescentic in outline, not flattened 



Trixosarcophaga, gen. nov. 

 Parafacialia only a little over half as wide as clypeus ; first 

 hypopygial tergite more or less flattened and concealed . 



Oxysarcodexia, gen. nov. 



30— Parafacialia broader than clypeus Wohlfahrtiopsis T. 



Parafacialia not as wide as clypeus 31 



31 — Arista long-plumose nearly or practically to tip ; or, if some- 

 times short of tip, the eyes large and cheeks scarcely ex- 

 ceeding at most one-fourth eye-length in breadth .... 32 

 Arista plumose not over three-fourths way, the cheeks fully 



or over one-third eye-length 33 



32 — Frontalia broader than parafrontalia in middle; cheeks 

 nearly one-half eye-length in width ; first hypopygial ter- 

 gite showing posteriorly a vertical slit bordered with partly 

 decussate spines, its disk broadly scooped out . Paraphrissopoda T. 

 Frontalia scarcely as wide as parafrontalia in middle; cheeks 

 about one-fourth eye-length ; first hypopygial tergite folded 

 but not slit on median line • Sarcodexia - T. 



