LOCAL AVIFADNiE OF THE GKKAT BASIN, 321 



the foot-hills and lower slopes of the higher and more fertile ranges, they 

 may be occasionally visited by several species from the pine-region higher 

 up, or from the adjacent canon slu-iibbery. The following-, however, are 

 particularly charactefistic of the cedar and nut-pine groves: — 



1. Myiatlestes townscudi. 



2. Sialia arctica. 



3. Lophopbanes iuornatns. 



4. Lanivireo pUiinbeus. 



5. Collurio exciibitoroides. 



G. Spizella arizona;. 



7. Scolecopbagus c^'anocepbalus. 



8. Gymnokitta cyanocepbabi.' 



9. Empidonax obscunis. 



3. Birds of the aspen groves and copses. — The aspens (Populus trem- 

 uloides) occiu' only on the higher, well-watered ranges, commonly in the 

 upper cailons, in moist and sheltered situations just below the fields or 

 patches of perpetual snow. The slender trees composing these groves or 

 copses are seldom large, never, except perhaps on certain of the more 

 eastern ranges, exceeding 30 or 40 feet in height, and usually not more than 

 half so tall. They are of straight, clean habit, however, with a smooth 

 whitish-green bark, and are carpeted underneath by a varied herbaceous 

 growth, among which beautiful ferns are sometimes conspicuous. The 

 characteristic birds of the aspens are not numerous, the following being all 

 that were noted: — 



1. Tardus migratorius. 



2. Progne subis. 



3. Helaiintbopbaga celata. 



4. Empidonax obscurus. 



5. Empidonax bammondi. 



C. Picus gairdueri. 



7. Spbyrapicus uucbalis. 



Several of the above, or all with the exception of the last three, and 

 nelminthophaga celata, are rather to be considered as species of general and 

 variable range, since they may sometimes be found in very considerable 

 abundance in other wooded localities. 



4. Birds of the canon shrubbery. — Several of the higher ranges of the 

 Interior receive sufficient precipitation, or retain throughout the summer 

 snow enough near their summits, to supply the main ravines and canons 

 with constant streams of water; and these nourish a thrifty or often luxu- 

 riant shrubby growth along their banks, where many species of birds resort, 



* Tbis species wo believe to be entirely peculiar to tbese woods, its food appar- 

 ently consisting exclusively of tbe seeds and berries of the nut-pine and cedar. 

 21 P u 



