Perching Birds Chiefly Brown or Streaked 



757. Gray-cheeked Thrush {Hylocit h la altcice). L. 

 7.5; W. 4. Ads. Tail and back the same color, olive 

 without brownish tinge; eye-ring and lores whitish, 

 cheeks and breast only slightly tinged with buff, breast 

 with wedge-shaped spots. Notes. Doubtless like 

 those of No. 757a. 



Range.— Breeds in Labrador and west to Alaska; migrates through 

 eastern North America and winters in Central America. 



757a. Bicknell Thrush (H. a. bicknelli). Similar 

 to No. 757, but smaller, L. 7; W. 3.5. Notes. Calls, 

 pbeu like that of Veery; a low cluck like that of Hermit 

 Thrush, and rarely, a pip or peenk like that of Olive- 

 backed Thrush; song, like that of Veery but more in- 

 terrupted. (Brewster.) 



Range.— Breeds in the high parts of the Catsklllls and north to 

 White Mountains and Nova Scotia; winters in tropics. 



758. Russet-backed Thrush (Hylocicbla ustulata). 

 L. 7.2; W. 4. Tail not decidedly more rufous than 

 back. Ads. Eye-ring, cheeks, sides of neck and 

 breast distinctly huffy, breast with wedge-shaped spots; 

 back and flanks olive-brown; tail slightly browner. 

 The most deeply colored bird of the ustulata group. 



Range. — Pacific coast; 

 south to Guatemala. 



breeds from Oregon to Alaska; winters 



7 58a. Olive-backed Thrush (H. u. swainsonii) . 



Similar to No. 758, but back, tail, and flanks without 

 brownish or rufescent tinge. Notes. Call, a liquid 

 putt', song, suggesting both that of Hermit Thrush and 

 the Veery. 



Range. — Eastern North America; breeds In Alleghanies from Penn- 

 sylvania and the Catskills, north to New Brunswick and Manitoba; 

 winters in Central and South America. 



758b. California Olive-backed Thrush (H. u. 



cedica). Differs from 758 and 758a, in more rufescent 

 coloration on the flanks; sides and upper surface 

 usually paler than No. 758. (Oberholser.) 



Range. — California, except north coast; north In Interior to southern 

 Oregon; south, In winter to Arizona and southern Mexico. (Ober- 

 holser.) 



7 58c. Alma Thrush (H. u. almce). Similar to No. 

 758a, but back and flanks grayer. The palest bird of 

 the ustulata group. 



Range. — Alaska, except Yukon Basin, south in Rocky Mountain 

 region, and west to Utah and eastern Neva H " 'V O. V.) 



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