35° 



NORTH AMERICAN DII'TKRA. 



Fig. 143. Peckia prtrceps, enlarged. 



TABLE OF GENERA. 



1. First posterior cell closed or much narrowed in the margin. 2 

 First posterior cell open. 5 



2. Second and third abdominal segments with discal and marginal 



macrochaetae Paramintho. 



Second and third segments without discal macrochaetae. . 3 



3. First vein bristly Johnsonia. 



1'irst vein bare. ......... 4 



4. Arista bare or pubescent. . . . . Hesperomyia. 

 Arista distinctly plumose. .... Sarcophilodes. 



5. Abdomen black or metallic, unicolorous and but slightly pruinose. 6 

 Abdomen gray or partly ochraceous, with black reflecting sjxUs. 8 



6. Hypopygium very prominent; legs more or less hairy, . 7 

 Hypopygium concealed; legs not hairy; curvature of fourth vein 



with an obtuse angle and without stump. . . Onesia. 



7. Abdomen usually black; tibia; densely hairy. . . Peckia. 

 Abdomen metallic; tibiae with short hairs (see Muscidae). 



Cynomyia. 



