306 



XORTH AMERICAN DIPTERA 



Family Micropezidse 



Slender flies of moderate size, their legs Jong, the second basal cell 

 united with the discal cell. 



Head orbicular or elongate and subtriangular; front without bris- 

 tles; face receding, without oral vibrissas; antennas short, the arista 

 dorsal. Thorax elongate, the front and middle coxae widely separated; 

 posterior portion of the pteropleura with long hairs; one sternopleural 

 bristle. Legs long and slender, the tibiae with bristles. Wings long, the 

 second basal cell united with the discal cell; apical cell narrow^ed or 

 closed and petiolate apically; auxiliary vein not distinctly separated 

 from the first vein. Abdomen long and slender, the female ovipositor 

 large, pendulous; male genitalia rather small, the fifth sternite usually 

 with long pendulous lobes. 



The adults are found in marshes and moist places in woods. There 

 are three or four Nearctic, one Pal^earctic and many species in the 

 American tropics. I have seen only Micropeza from the United States 

 and Canada. The immature stages are unknown. Enderlein* has re- 

 viewed the family. I give the characters of his genery although I 

 scarcely agree that there are four genera represented. The appendicu- 

 late apical cell does not seem to me to be of generic importance and 

 I am inclined to recognize only Micropeza and MetopohracJiia. 



Micropezidse. — 1, 2, Micropeza; 3, 4, Metopobrachia. 



