122 



YOSEMITE NA rURE NOTES 



to which it bears sonic resemblance. 

 Often jerks its wings nervously. 



Frequents chielly dense well-shaded 

 forests where the ground is leaf-littered 

 but largely unobstructed by close 

 growth of bushes. S. V. in the Sierra 

 chiefly in the Transition and Cana- 

 dian life-zones, but also in the lower 

 Hudsonian life-zone. \V. V. below the 

 level of h(>avy snows. Occasionally nests 

 on the floor of Voseniite Valley but 

 more conuuon at higher elevations as 

 at Mariposa Grove, Glacier Point, and 

 Tuolumne Meadows. 



SU'AISSON'S THRUSH (Hylo- 

 cichla ustulata): 6/2 - V/a in. Above 

 gray or olive-brown; wings and tail 

 somewhat darker; no rust in tail; belly 

 white: sides tinged with brown; upper 

 breast li'J,ht hu'J spotted icith iced'^c- 

 shaptd morks: eve - ring and cheeks 

 buHy. 



Fre(|uents willows, aspens, alders, and 

 other dense growth along streams and 

 about damp meadows. Enters the damp 

 understorv vegetation of cK'nse forests. 

 Ghii-fly in the Upper Sonoran, Transi- 

 tion, and Canadian life-zones. Common 

 S. \'. largely throughout, west of the 

 desert divides. WidesjJread M. S. V. 

 (liiefl\- in the Transition zone in the 

 \'osemite region. Has nested in Vo- 

 seniite \'allev; often seen near Mirror 

 Lake. 



MEXICAN BLUEBIRD (Sialia 

 mexicana): 6^2-7 in. Above dark blue 

 except sometimes for rust area in mid- 

 dle of back; breast runy grading into 

 gray on belly; tail slightly forked. Fe- 

 male: Above gray or brownish, tinged 

 with blue; wings blue, with light bars; 

 breast faintly rusty. Nests in abandoned 

 woodjx'cker holes or other cavities. 

 Feeds on mistletoe and other berries 

 and on insects. 



Frequents broken well-spaced timber, 

 open woodland, or brushland. When 

 breeding found chiefly in the UpjDer 

 Sonoran and Transition life-zones but 

 enters adjacent zones. Spreads to low- 

 lands in winter. Likely to be seen at 

 any time of the year in the western 

 foothills in the Yosemite region. In- 

 fall seen at higher altitudes as in ^'o- 

 semite Valley and in higher locations. 



MOUNTAIN BLUEBIRD (Sialia 

 currucoides): ^Yi-iy.^ in. Almost en- 

 tirely blue, lighter below, grading to 

 whitish on belly; tail forked. Female: 

 Soft gray-brown above, tinged with 

 blue; rump, tail, and wings bluish. 



Frec]uents chiefly open terrain of 

 short grass or turf where rocks, scat- 

 tered bushes, or small trees provide 

 perches. In the Sierra. S. V. in high 

 Transition to the Hudsonian life-zone, 

 especially the latter. Of irregular oc- 

 currence in the lowlands in winter. In 



MEXICAN BLUEBIRD TOWNSEND'S SOLITAIRE 



