DESCRIPTION OF CAMPS. 333 



species were noticed from the very beginning of the open country, on the 

 outskirts of the city, to the first foot-hills of the Sierra Nevada. 



3. The Sierra Nevada (July 6-12). — The rolling plains became so 

 gradually modified into more pronounced undulations, and these so imper- 

 ceptibly into decided hills, that there was no abrupt change noticeable in 

 either the fauna or the flora. With the first pine trees, however, were 

 observed the Robin (Turdus migrator'ms), the California Bluebird {Sialia 

 mexicana), and Brown Creeper (Certhia americana); while among the thick 

 chapan-al of the ravines and hill-sides the following species were seen for 

 the first time: — 



a. Western foot-hilh (July C-7). 



1. Psaltriparus minimus. 



2. Polio[)tila (cterulea?) 



3. Chrysomitris lawreucii. 



4. Pipilo crissalis. 



5. Lopbortyx californicus. 



These species were not seen near the summit, but were gradually left 

 behind as we ascended the now steeper slopes and entered a denser forest, 

 where large and lofty coniferaj became exclusive. The three species pre- 

 viously mentioned, however, continued with us during the journey. As was 

 the change from the plains to the foot-hills a very gradual one, so did the 

 mixed woods and chapairal of the latter, in which deciduous trees and 

 shrubs abounded, become as imperceptibly transformed into denser and 

 loftier forests, where conifersB first greatly prevailed and then constituted 

 the entire sylva. The change was indeed so gi-adual that we could detect 

 no well-defined point where there was a marked difference in the birds 

 observed; one species after another being left behind, while one by one new 

 ones made their appearance, so that it was found impossible to fix a bound- 

 ary-line between two regions. The "Mountain Jay" {Cyanura frontalis) 

 was met with long before we lost sight of the "Valley Jay" {Cyanocitta 

 californica), and the "Valley Quail" (LopJiortyx californicus) was common, 

 and leading its young, in ravines, beside which the pines resounded with 

 the screams of the Mountain Jay and Nutcracker {Picicorvus Columbian ua) 

 and the tapping of pinicolino Woodpeckers I^S2)hyra2)icus ruber and Picus 

 albolarvatus). 



