Vol. XI] COLE AXD LOVETT— LIST OF OREGON DIPTERA 279 



470. Chilosia nigripennis Will. 

 Mt. Jefferson, VII-15 (Bridwell). Bigot also reported 

 it from Mt. Hood as Cartosyrphus infumatus. 



471. Chilosia nigrovittata Lovett 

 Corvallis, IV-22 (Neilson). 1919, Proc. Cal. Acad. Sci., 

 Ser. 4, IX, p. 239. 



472. Chilosia occidentalis Will. 

 Mary's Peak 111-30 (Black). 



473. Chilosia nigro-ccerulea Lovett 

 New name for pacifica Lovett. Lava Lake, VII-15 

 (Lovett) ; Mt. Jefferson, VII (Bridwell) ; Corvallis, V-17. 

 1919, Proc. Cal. Acad. Sci., Ser. 4, IX, p. 240. 



474. Chilosia pallipes Loew 

 Mt. Jefferson, Horse Lake, VI 1-25 (Bridwell) ; Mt. Jef- 

 ferson, VIII-1; Mary's Peak, V to VII (Lovett). Occurs 

 at lower altitudes in scattering numbers. A very common 

 form in higher altitudes in midsummer in blossoms of Helle- 

 bore. 



475. Chilosia parva Will. 

 Described from Oregon. 



476. Chilosia petulca Will. 

 Mary's Peak, VI (Lovett). 



477. Chilosia signatiseta Hunter 

 Hood River, V-5 (Cole). 



478. Chilosia sororcula Will. 

 Mary's Peak, V-9 (Currey). 



479. Chilosia versipellis Will. 

 Hood River, V- 19 (Cole). 



480. Chilosia willistonii Snow 

 Corvallis (Bridwell) ; Hood River, V-8 (Cole). 



