Vol. XI] COLE AND LOVETT—LIST OF OREGON DIPTERA 227 



Family SIMULIID^ 



Fig. 11. Prosimulium fulvum (Coq.) 



These tiny flies are easily recognized and are variously 

 known as black-flies, buffalo gnats and sand-flies. The 

 females "bite", as many are willing to testify, and are some- 

 times very troublesome to stock and man. The larvae live 

 in running water, often in swift currents, and feed on small 

 animals and algae. Peculiar fans on the head create a current 

 toward the mouth. They are anchored to rocks by a suck- 

 ing disc near the tail and by a silken line, and breathe by 

 means of a peculiar organ near the tip of the body; the 

 larvae move like geometrid larvae. 



149. Prosimulium fulvum (Coq.) 

 Pamelia Lake, Mt. Jefferson, elevation 3,000 feet. (Brid- 

 well). Malloch det. 



150. Prosimulium hirtipes (Fries.) 

 Sand Mountain, VI-20; Dee, VI-17 (Cole); Forest 

 Grove, IV-20 (Cole); Mt. Jefferson, VII-15 (Bridwell). 

 Malloch det. 



151. Simulium bivittatum Mall. 



Hood River (Cole) . Very common in July in the willow 

 flats along the Columbia River. They make their appear- 

 ance about sundown and late bathers then are glad to put 



