lis NOirni AMKIUOAN DIl'TKRA. 



2. "Wings very narrow in proportion to their lonj;tli, of equal width, broad- 



ly rounded at base and tip. . . . Ptkrocalla Kondani. 

 Wings witli an unusually convex j)osterior margin. Callopistisia Loew. 



3. Anterior and posterior cross-veins very oblique, not approximated 



(Mexico). ....... Mtennis Desvoidy. 



Posterior cross-vein rectangular or nearly so. ..... 4 



4. Second longitudinal vein straight or nearly so ; anterior cross-vein not 



oblique. ........... 5 



Second longitudinal vein markedly sinuous ; cross-veins approximated 

 and the anterior one very oblique.* Paragorgopis Giglio-Tos. 



•5. Cheeks rather broad ; posterior angle of anal cell acute. 



Stictocephala Loew. 



Clieeks and face extremely short ; eyes transversely oval ; posterior 



angle of anal cell rectangular (New Mexico). Psairoptera Loew. 



ulidiin.eX^ 

 Head large, liemispherical ; proboscis stout, with broad labella; front 

 broad; antennte short; mesonotum bristly in the middle behind only; first 

 and third longitudinal veins of the wings bare, the third and fourth con- 

 vergent distally ; posterior angle of the anal cell acute, sometimes drawn 

 out into a long lobe. 



1. Head conspicuously large ; front unusually broad and the antcnn.T very 



widely sei)arated. ......... 2 



Head not conspicuously large, the antenna' more ajiproximated at their 

 root. ...........'■) 



2. Third anteniuil joint round ; front i)unctulate. . . (Edopa Loew. 

 Third antennal joint elongate; upper ])art of front rugose. 



Eurvcephai.a Ra'der. 



;l. Posterior angle of anal cell acute, but scarcely prolonged lobe-like. 8 

 Posterior angle of anal cell distinctly drawn out into a lobe. . 4 



4. Front punctate or scrobiculate. ....... o 



Front snu)oth, . . ......... 7 



5. Scutellum flat, with sharp edges ; fourth longitudinal vein strongly 



curved forward at its end ; front coarsely rugose. 



Notogramma Lot'w. 

 Scutellum convex, rounded on its edges. ..... 



(!. Stigma not unusually elongate Ui.idia Meigen. 



Stigma elongate, about as long as the costal cell. Acrosticta Loew. 



* This genus is locati'd here as definitely as the characters given will 

 ])ermit. , 



12 1' ^^..-v-^T-^ (eU.-v^l-«i— ^ 



