Vol. XI] COLE AND LOVETT— LIST OF OREGON D1PTERA 283 



510. Syrphus intrudens O. S. 

 Mt. Jefferson; Mary's Peak (Bridwell and Lovett) ; 

 Hood River, V-20 (Cole). Fairly common in higher alti- 

 tudes during August. 



511. Syrphus maculifrons Bigot 

 Described from Oregon. 



512. Syrphus mentalis Will. 



Tillamook, 111-26 (Burrill); Rock Creek, 111-20 

 (Lovett). Type from Washington Territory. A rare 

 species. Two males which I am satisfied belong here vary 

 from the female in certain minor respects and the following 

 notes are appended. 



Male. Similar in general appearance and markings to 

 the female, everywhere tending to be darker and with more 

 elongate pile. Frontal triangle swollen, pile black, coarser 

 and longer than in female. Antennae darker, but, as in 

 female, set in yellow field. Dark facial stripe much broader, 

 the yellow on sides narrow and obscured by gray pollen. 

 Pile on face elongate, black; cheeks black, narrowly yel- 

 lowish below oral margin. 



Abdominal cross bands similar in appearance to female, 

 first and third do not reach lateral margins though this is 

 evidently a variable character. Legs black, briefly brown 

 at union of femora and tibiae. Pile black, elongate. 



513. Syrphus opinator O. S. 

 Common. See note under americana. 



514. SyTphus pacificus Lovett 

 Corvallis (Lovett) ; Hood River, V (Cole). 1919, Proc. 

 Cal. Acad, of Sci., Ser. 4, IX, p. 245. 



515. Syrphus perplexus Osburn 

 Burns, V (Thompson) ; Philomath, V; Mary's Peak, VIII 

 (Lovett). 1910, Jl. N. Y. Ent. Soc, XVIII, p. 55. 



516. Syrphus protritus O. S. 

 Grant Co., one specimen, no other data. 



