no. 2070. PARASITIC AND PREDACEOUS DIPTERA— WALTON. 173 



All types and specimens mentioned herein are deposited in the 

 United States National Museum in Washington. 



Since the insect fauna of the region explored is very little known 

 a list of the species collected is included together with such annota- 

 tions as are deemed of importance. 



Family NEMXSTRINIDAE. 



RHYNCOCEPHALUS VOLATICUS Williston. 



One specimen of this rare fly collected from awning in camp by 

 Mr. Donald J. Caffrey, July 28. 



Family BOMBYLIIDAE. 



Genus EXOPROSOPA Maequart. 

 EXOPROSOPA ROSTRIFERA Jaennicke. 



Exceedingly abundant everywhere on the mesa. 



EXOPROSOPA DORCADION Osten Sacken. 



Common but difficult to approach. 



EXOPROSOPA PUEBLENSIS Jaennicke. 



One specimen, July 30. 



Genus ANTHRAX Seopoli. 

 ANTHRAX LATERALIS Say. 



Very abundant on mesa. 



ANTHRAX ALCYON Say. 



Common during early August. 



ANTHRAX BIGRADATA Loew. 



One specimen August 5. 



ANTHRAX EDITIA Say. 



Common during early August. 



ANTHRAX MOLITOR Loew. 



One specimen August 6. 



ANTHRAX ANNA Coquillett. 



Abundant on mesa from late July to August 10. 



ANTHRAX CYRTIS Coquillett. 



Two specimens August 7; mesa. 



Genus PHTHIRIA Meigen. 

 PHTHIRIA SULPHUREA Loew. 



Two specimens on flowers of Grindelia near irrigation pond July 3 1 . 

 Genus TOXOPHORA Meigen. 



TOXOPHORA PELLUCIDA Coquillett. 



One specimen from border of irrigation pond July 21. 



Genus GERON Meigen. 



GERON SENILIS Fabricius. 



Abundant on mesa during early August. 



