WRENS, THRASHERS, ETC. 435 



7'. Back rusty brown. 



Thryothorus, p. 440. 



Fig. 550. 



GENUS OROSCOPTES. 



702. Ol'OSCOptes montanus (Towns.). SAGE THRASHER. 



Bill much shorter than head ; rictal bristles well developed ; wings and 

 tail of equal length ; tail nearly even. 

 Adults: upper parts dull grayish 

 brown, indistinctly streaked ; wings 

 with two narrow white bars ; tail with 

 inner web of 2 to 4 outer feathers 

 tipped with white ; under parts whitish, 

 buffy on flanks and under tail coverts ; breast and sides heavily marked 

 with black spots. Young : like adults, but upper parts indistinctly streaked 

 with darker, and streaks on under parts less sharply defined. Length : 8- 

 9, wing 3.95-4.19, tail 3.20-3.35, bill .60-.65. 



Distribution. Sage plains from Montana south to northern Mexico and 

 Lower California, and from western Nebraska to the Cascades and the 

 Sierra Nevada. 



Nest. Bulky, composed largely of coarse plant stems, dry sage 

 shreds, and sage bark, lined with fine rootlets, and sometimes hair ; placed 

 usually in sagebrush. Eggs : 3 to 5, rich greenish blue, spotted with clove 

 brown. 



The sage thrasher, and the Brewer, Bell, and lark sparrows, are 

 among the commonest birds of the sagebrush country, and the sage 

 thrasher's big gray body with its white tail corners shows from a 

 distance as he disappears with long undulating flight over the face 

 of the sage plain. 



In the land of telegraph poles he often mounts one to sing, but 

 his commonest perch is the top of a tall sage bush, and as his song 

 is poured out even long after dark and sometimes by moonlight, 

 with scarcely less richness than the true thrasher's, you are glad he 

 lives in the deserts. In winter he leaves the sagebrush and wanders 

 south over the lower valleys. 



GENUS MIMUS. 



703a. Mimus polyglottos leucopterus (Vigors). WESTERN 

 MOCKINGBIRD. 



Bill much shorter than head, notched near end ; rictal bristles well 

 developed ; wings rounded ; tail longer than wings, rounded ; tarsus longer 

 than middle toe and claw : scales of tarsus distinct. Adults : upper parts 

 grayish drab ; wings and tail blackish, wings with large white patch at base 

 of primaries, wing bars, white-tipped wing quills, and tertials with whitish 

 edgings ; under parts white, washed with clay color. Young : more brown- 

 ish above ; back indistinctly spotted or streaked : breast spotted. Male : 

 wing 4.29-4.72, tail 4.53-5*32, bill .61-.75. Female : wing 4.25-4.65, tail 

 4.43-5.08, bill .59-.71. 



Distribution. Southwestern United States from the Gulf of Mexico 



