DESCRIPTION OF CAMPS. 



359 



constantly exposed to the sun. The woods of this range begin at the base 

 of the "spurs" between tlie canons, and continue, in successive belts, to 

 the timber-line, as follows: From the valley level, thick and extensive 

 Avoods, composed exclusively of cedar and pinon, extend for 2,000 or 2,500 

 feet, when they gradually give way to more scant groves of mountain 

 niahogan}- {Cercocarpus ledifoliiis), which, however, scarcely extend higher 

 than 3,500 feet above the valley. Beyond this altitude no trees of these 

 species are met with, for on the higher peaks they are replaced by forests 

 of pines {Pimis flexilis and P. baJfouriana), with an undergrowth of hardy 

 shrubs. These pine trees are not tall, the highest not exceeding thirty or 

 forty feet, but they have trunks of comparatively large size ; and it was 

 observed that when growing in situations where exposed to the wind, which 

 here constantly bloAvs from one direction, all the branches of these trees 

 are bent away from the wind, or, indeed, grow only upon that side, while 

 the shrubs underneath are pressed flat to the ground in the same direction. 

 During our investigations among these mountains, the following species 

 were observed, between July 12 and the 5th of September: — 



tShnibbery of canon streams. 



Ictei iu loDgicaiula 



Gcothlypis uiacgillivra.yi 



M\iodioctes pusillus 



Dendrceca ^estiva 



Melospiza fallax .... . . 



. .Bare. 

 . .Abundant. 

 . - Rare. 

 . . Common. 

 . . Bare. 



Cyauospiza aiuoena Common. 



Pipilo uiegalonyx Very rare. 



Pipilo cliloriirus Common. 



Icterns bullocki . . Common. 



Empidouax pusillus Common. 



Hedymelesnielaaocephalus.OoHiw!o«. 



Loicer woods. 



Icterus bullock 



Turdus migratorius Common. 



Parus moutanus Bare. 



Psaltriparus plumbeus Bare. 



Psaltriparus melauotis? ... One specimen. 

 Troglodytes parkinanni . . . Common. 

 Helminthopbaga virginite. . Common. 



Dendrceca iiigrescens Common. 



Pyranga ludoviciana Common. 



Lanivireo plumbeus Common. 



Vireosylvia swaiusoni Common. 



Colluiio excubitoroides Common. 



Carpodacuscassiui(Aug.lO)A6MMdaMi. 

 Loxia leucoptera (Aug. {'2) . One specimen. 

 Spizella arizonae Very abundH. 



Common. 



Scolecopbagus cyauocepba- 



lus Common. 



Piclcorvus columbiauus Bare. 



Gymnokitta cyanocephala. . Bare. 



Cyanocitta woodhousii Bare. 



Tyranuus verticalis Abundant. 



Myiarchus ciuerasceus Common. 



Contopus ricbardsoui Common. 



Empidouax obscurus Common. 



Ohordeiles benryi.'. Abundant. 



Picus harrisi . Bare. 



Colaptes mexicauus Bare. 



Zenaedura carolinensis .Abundant. 



