Perching Birds Chiefly Brown or Streaked 



757. Gray-cheeked Thrush (Hylocichla aliciai). 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. 7573. 



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. Breads In the high parts of the Catskillls and north to 

 White Mountains and Nova Scotia; winters in tropics. 



758. Russet-backed Thrush (Hvlocichla ustulcta}. 

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

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

 breast distinctly buffy\ 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; breeds from Oregon to Alaska; winters 

 south to Guatemala. 



758a. 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 7583, 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.) 



758c. Alma Thrush (H. u. alnwi). Similar to No. 

 7583, 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 Nevf"*- ' V O. U.) 



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