582 ANIMAL LIFE IN THE YOSEMITE 



After the broods leave the nest, the families range about locally and 

 some groups undertake a more extensive wandering which may lead them 

 well up into the mountains. In 1915 the movement had carried at least 

 one flock to Yosemite Valley by July 27. A flock of 12 was seen on that 

 date making rapid time eastward through the golden oaks along the base 

 of the north wall. On July 30 a flock of 8 was noted near the Tenaya trail 

 where it leads down near Mirror Lake, and on various dates in August 

 and September flocks of bush-tits were seen or heard in trees and brush 

 bordering the several trails which ascend the Valley walls. By late fall 

 the birds have returned to the foothills, our latest record for the species 

 above its foothill range being for October 11, 1914, when some were heard 

 on the Tenaya trail at about the 5700-foot level. 



In 1920 bush-tits were observed by Mr. C. W. Michael (MS) in the 

 Valley on various dates through the fall months, from August 29 even to 

 as late as December 27. On the latter date "the largest flock yet seen" 

 (17 birds at least) was encountered. 



This species was discovered once east of the Sierras. A flock of bush- 

 tits was encountered near Williams Butte on September 22, 1915, and 

 the one individual shot proved to be a California Bush-tit; whether the 

 remainder comprised this species or the Lead-colored Bush-tit was not 

 learned. The former is not known to occur regularly on the east slope 

 of the mountains in this latitude and this may be an extreme case of 

 up-mountain, or rather, cross-mountain wandering from the west slope. 



Lead-colored Bush-tit. Psaltriparus plumbeus (Baird) 



Field characters. — As for California Bush-tit (which see), but top of head gray like 

 back. Voice: Like that of California Bush-tit. 



Occurrence. — Eesident east of Sierra Nevada. Eecorded at Williams Butte, Sep- 

 tember 22, 1915. Lives in low trees. In flocks except when nesting. 



The Lead-colored Bust-tit was encountered by us on only one occasion. 

 On the morning of September 22, 1915, a small flock which comprised both 

 adult and immature birds was observed in the piiion pines on Williams 

 Butte. In both voice and mannerisms these bush-tits resembled closely the 

 California Bush-tit, a species which, curiously, had been encountered pre- 

 viously the same day. 



Pallid Wren-tit. Chamaea fasciata hensKawi Ridgway 



Field characters. — Size nearly that of Junco; tail long, exceeding body in length, 

 slender, rounded at end, and habitually carried up at decided angle with back. Color- 

 ation grayish brown above, pale brown beneath; iris white. Voice: Common call a 

 series of clear whistled notes all on nearly or quite the same pitch, uttered slowly at first 

 then more rapidly, running into a trill, pit, pit, pit, pit-tr-r-r-r-r; also a subdued, 

 ratchet-like note, repeated in series. 



