422 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.58. 



Genus GNOPHOMYIA Osten Sacken. 



KEY TO SPECIES. 



Wings pubescent apically; halteres entirely black G. liictuosa (p. 422). 



Wings vvitliout an apical pubescence ; knobs of the halteres yellow 



G. tristissima (p. 422). 



The immature stages of the known species are spent beneath the 

 bark of decaying trees. 



GNOPHOMYIA LUCTUOSA Osten Sacken. 



Dead Run, Virginia, E. C. Shannon; Falls Church, Virginia, 

 August 16, 1916, Tom Ketcher. 



•GNOPHOMYIA TRISTISSIMA Osten Sacken. 



Abundant; extreme dates of capture. May 5 and October 28; in 

 copula, June 18; bred from tulip tree bark. May 5, 1913, R. C. 

 Shannon. P. I. 



Genus TRIMICRA Osten Sacken. 



* TRIMICRA ANOMALA Osten Sacken. 



Maywood, Virginia, October 16, 1915, at light, McAtee. The im- 

 mature stages are spent in moist earth. 



Genus ORMOSIA Rondani. 



KEY TO SPECIES. 



1. Wings spotted or clouded with darker 2. 



Wings unicolorous or nearly so, the stigma only being darker 3. 



2. Anal veins convergent; wings with numerous dark brown dots 



O. innocens (p. 422). 



Anal veins divergent ; wings with pale clouds of dark-colored hairs 



0. nubila (p. 423). 



3. Cell first If: closed 0. nigripila (p. 423). 



Cell first 3/2 open 4. 



4. Cell first Mi confluent with cell ilfs, the outer deflection of Ms lacking 5. 



Cell first M2 confluent with cell Mz, m lacking 0. holotrlcha (p. 422). 



5. Thorax reddish, stigma indistinct O. rubella (p. 423). 



Thorax gray, stigma distinct 6. 



6. Gonapophyses of male hypopygium minutely serrate 0. scrridens (p. 423). 



Gonapophyses not serrate 0. mcigenii (p. 423). 



The immature stages are spent in moist earth. 



• ORMOSIA HOLOTRICHA Osten Sacken. 



Described from specimens collected at Washington, District of 

 Columbia. 



* ORMOSIA INNOCENS Osten Sacken. 



Dead Run, Virginia, April 19, 1914, R. C. Shannon. 



