444 NORTH AMERICAN DIPTERA 



Abdomen in both sexes wide and deep, the terminal segment large, 

 normally concealing the genitalia within a slit-like opening. 



*Pateloa Townsend 



198. Middle coxje of female with normal bristles; males without orbitals. .199 

 Middle coxse of female with closely placed, curved apical spines; males 



with two pairs of orbitals (136, 137, 153, 175). 



Doryphorophaga Townsend 



199. Posterior sublateral bristle present 200 



Posterior sublateral absent fPhorocera Desvoidy 



200. Abdomen with discals 201 



Abdomen without discals Euthelaira Townsend 



201. Ocellars long and strong 202 



Ocellars weak; posterior presutural acrostical absent. 



Eupelecotheca Townsend 



202. Ocellars proclinate 203 



Ocellars reclinate Coloradalia, n. g. 



203. Anterior tibiae with two posterior bristles; apical cell ending far be- 



fore the wing- tip (Amphichaeta B. B.) tP^iorocera Desvoidy 



Anterior tibiae with a single posterior bristle; apical cell ending close 

 to the wing-tip (170, 194) Oxynopsalia, n. g. 



204. Not metallic green or blue 20G 



Metallic green or blue 205 



205. Oral margin strongly produced Chlorotachina Townsend 



Oral margin scarcely produced (56) Gymnochaeta Desvoidy 



206. Pteropleural bristle of normal length or weak, if long the para- 



frontal s are shining black or the frontal bristles do not extend 



below the base of the arista 209 



Pteropleural very long and strong, extending to the apex of the 

 squamae; frontals usually extending to the middle of the third 

 antennal segment; parafrontals pollinose 207 



207. Male without orbitals; parafacials almost or fully half as wide as 



third antennal segment 208 



Male with orbitals; parafacials below not over one-foui'th as wide as 

 the elongate third antennal segment; front wide in both sexes. 



Homalactia Townsend 



208. Frontal bristles extending to the middle of the parafacials. 



Lypha Desvoidy 

 Frontals not extending below the base of the arista. Hineomyia Townsend 



209. Parafrontals pollinose 210 



Parafrontals bare; pteropleural long; apical cell terminating near the 



wing-tip; abdomen shining black Polidaria n. g. 



210. Fifth longitudinal vein bare 212 



Fifth longitudinal vein setose 211 



* Aldrich and Webber. 1924, Pr. U. S. N. M., Ixiii, Art. 17, pp. 45, 51 (Phorocera). 

 t Aldrich and Webber, 1924, Pr. U. S. N. M., Ixiii, Art. 17, pp. 45, 51. 



