FAMILY TACHIXID.B THE TACHINIDS 447 



239. Apical cell open or closed in the wing margin (3, 46). 



Spallanzania Desvoidy 

 Apical cell rather long petiolate Aravaipa Townsend 



240. Arista plumose or strongly pubescent, the clypeal region as long as 



the distance from the upper pair of vibrissas to the antennal base. . .249 

 Arista bare or weakly pubescent; oral margin produced and not nar- 

 rowed 241 



241. Apical cell petiolate 242 



Apical cell open 243 



242. Prosternum bare Neometachaeta Townsend 



Prosternum with hair and a long bristle on the sides. .Epidexia Townsend 



243. Palip absent or very slender on their whole length 244 



Palpi normal, enlarged apically 247 



244. Palpi extremely short or absent, never more than twice the length of 



the thickness of the proboscis at point of attachment 245 



Palpi elongate and slender, very rarely short; parafacials always with 

 two or more bristles below (7) *Peleteria Desvoidy 



245. Parafacials with one or more bristles below (39, 61) .Cuphocera Macquart 

 Parafacials without bristles below 246 



246. Abdomen without discal bristles Euepalpus Townsend 



Abdomen with discal bristles on intermediate segments. 



Xanthozona Townsend 



247. Parafacials with one or more bristles in addition to the hair. 



Chaetoprosopa Townsend 

 Parafacials with fine hair only Chaetoprocta Brauer & Bergenstamm 



248. Clypeal region not long and narrow, short and not conspicuous, cheeks 



rarely more than half as wide as the eye-height 251 



Clypeal region long and narrow; cheeks two-thirds as wide as the eye- 

 height 249 



249. Posterior sublateral bristle absent 250 



Posterior sublateral bristle present; sternites with at most weak 



bristles (99) tMicrophthalma Macquart 



250. Sternites with long, very strong bristles Megaprosopus Macquart 



Sternites without strong bristles Megaparia Wulp 



251. Palpi normal in shape and length 254 



Palpi absent or reduced to about half the normal length, wholly slen- 

 der and bearing only one or two apical bristles 252 



252. Apical cell open 253 



Apical cell long petiolate (115) Melanophora Meigen 



253. Palpi absent or extremely small; large, robust, Archytas-like species, 



the apical cell ending far before the wing-tip. . Vibrossomyia Townsend 

 Palpi about half the normal length; apical cell ending close to the 

 wing-tip Atrophopalpus Townsend 



* Curran, 1925, Trans. Roy. Soc. Canada, Section V, p. 226. 

 t Aldrich. 1926, Pr. U. S. N. M.. Ixix, Art. 13, p. 2. 



