42 PACIFIC COAST AVIFAUNA No. 10 



175. , . Nuttallornis borealis (Swainson) 



Olivk-sidEd Flycatci-iEr. 



Synonym — Contopiis borealis. 



Status — 'Common in summer from the Transition zone upward, in the higher 

 mountains north of the Mogollon Plateau ; recorded as breeding on the vSan Fran- 

 cisco, White, and Mogollon mountains. During the migrations it is quite -gen- 

 erally distributed. 



176. Myiochanes pertinax pallidiventris (Chapman). , , . 



CouES Flycatcher. 



Synonyms — Contopiis pertinax; Contopiis pertinax pallidiventris ; Horiso- 

 pus pertinax pallidiventris. 



Status — Common summer visitant in the Transition zone of the mountains 

 of southeastern Arizona CPTuachuca, Santa Rita, Santa Catalina and White 

 mountains, Mount Graham, etc.), extending northward, in diminishing numbers, 

 to the Mogollon Mountains, where it was found breeding at Baker's Butte 

 (Mearns, 1890a, p. 256); casually to Fort Whipple: i specimen, August 20, 

 1864 (Coues, 1866a, p. 60). 



177. Myiochanes richardsoni richardsoni (Swainson). 



Western Wood Pewee. 



Synonyms — Contopiis richardsoni; Contopiis virens richardsoni ; Horizopus 

 richardsoni ; Contopiis veliei. 



Status — Common in summer in Upper Sonoran and Transition throughout 

 the state. During the migrations it is generally distributed. 



178. Empidonax difficilis difficilis Baird. 



Western Flycatcher. 



Synonym — Empidonax flaviventris var. difficilis. 



Status — A fairly common summer visitant, mostly in Transition, occurring 

 in all the higher mountain ranges. Abundant and of general distribution during 

 the migrations. 



179. , Empidonax trailli trailli (Audubon). 



Traill Flycatcher. 



^ynorvyms-T—Empidonax pusillns; Empidonax trailli var. pusilliis. 



Status — Probably fairly common in summer along most of the wooded 

 streams in the lower valleys, though found actually breeding at but a few points : 

 Tucson, Fort Whipple, San Pedro River, Santa Cruz River. During the migra- 

 tions it is abundant and generally distributed. 



180. Empidonax hammondi (Xantus). 



Hammond Flycatcher. 

 Status — A migrant, abundant and generally distributed throughout the state. 

 It is not known to breed anvwhere in Arizona. 



