48 PROCEEDINGS OF THE NATIONAL MUSEUM vol.69 



Washington : Spokane, July 2, 1917 (H. G. Dyar). 



Glacier, June 4, 1917 (H. G. Dyar). 

 West Virginia : White Sulphur Springs, October 



25, 1915 (F. Knab). 

 Wyoming: Yellowstone Canyon, July 5, 1922 (H. 



G. Dyar). Old Faithful. June 27, 1922 (H. G. 



Dyar). 

 Yukon Territory : White Horse, July 1, 1919 (H. 



G. Dyar). Carcross, July 21, 1919 (H. G. Dyar), 



EXPLANATION OF FIGURES 

 Plate 1 



A. Profii milium hirtipes. Male genitalia, ventral view. 



B. Prosimilmm hirtipes. Female genitalia, lateral view. 



C. SimuHum vennstuni. Male genitalia, ventral view. 



I). Simtili/itm venustnm. Male genitalia, viewed from caudal aspect. 



E. EusimuUiim frisoni. (i. Genital fork : 1). terminal organs. 



F. ParasimuUmn furcatum. Wing. 



G. SimuUum Wing. 



Plate 2 



Fig. 1. Prosimulirm maf/niiin Dyar and Shannon, female ovipositor. 



2. The same, genital rod. 



3. Prosimulium exigens Dyjir and Shannon, female ovipositor. 



4. The same, genital rod. 



5. Prosimulium dicum Dyar and Shannon, female ovipositor. 



6. The same, genital rod. 



7. Prosimulium dicenUim Dyar and Shannon, female ovipositor. 



8. The same, genital rod. 



9. Prosimulium, fulvum Coquillett. female ovipositor. 



10. Prosimulium, oniichodnctiilum Dyar and Shannon, female ovipositor, 



11. The same, genital rod. 



12. Prosimulium hirtipes Fries, female ovipositor. 



13. The same, genital rod. 



Plate 3 



Fifi. 14. Prosimulium novum, Dyar and Shannon, female ovipositor. 



15. The same, genital rod. 



16. Prosimulium pancerastes Dyar and Shannon, female ovit)0.sitor. 



17. The same, genital rod. 



IS. Prosimulium pleurale Malloch, genital rod. 



19. EusimuUum johannseni (Hart), female ninth segment and cerci. 



20. Prosimulium fulvum Coquillett. male clasper. 



21. The same, male adminiculum. 



22. Prosimulium mngrnmi Dyar and Shannon, male clasper. 



23. The same, male adminiculum. 



24. EusimuUum braeteatum (Coquillett), male clasper. 



25. The same, male adminiculum. v 



26. The same, male adminiculum arms. 



