THE THRUSHES. 69 



Sialia arctica (Swains.) 



MOUNTAIN BLUEBIRD. 

 Popular synonyms. Arctic Bluebird; Rocky Mountain Bluebird. 



Erythaca (Sialia} arctica Sw. & RICH. F. B. A. ii, 1831, 209, pi. 39. 



Sialia arctica NUTT. Man. ii, 1834, 573; ed. 2, i, 1840, 514. AUD. Synop. 1839, 81: B. Am. i : , 

 1841, 176, pi. 136. BATED, B. N. Am, 1858, 224; Cat. N. Am. B. 1859, No. 160; Rev'ew, 18'U. 

 64.-COUES. Koy, 1872,76; Check List, 1873. No. 18; 2d ed. 1882, No. 29; B. N. W. 1874, 

 14; B. Col. Val. 1878. 8J. B. B. & R. Hist. N. A. B. i, 1874. 67. pi. 5, fig. 4. RIDGW. Norn. 

 N. Am. B. 1881, No. 24. 

 Sylvia arctica AUD. Orn. Biog. v, 1839, 38, pi. 393. 



HAS. Western mountain districts of North America, north to lat. 6J&. south nearly, or 

 quite, to the Mexican boundary, at high elevations. 



"Sp. CHAR. Greenish azure-blue above and below, brightest above; the belly and 

 under tail-coverts white; the latter tinged with blue at the ends. Female showing blue 

 only on the rump, wings, and tail; a white ring round the eye; the lores and sometimes a 

 narrow front whitish; elsewhere replaced by brown. Length, 6.25; wing, 4.3(j; tail, 3.00. 

 4875.) 



"Young. Male birds are streaked with white, as in S.sialis, on the characteristic 

 ground of the adult. 



"As already stated, the blue of this species is greener than in 

 sialis. The females are distinguished from those of the other spe- 

 cies by the greener blue, entire absence of rufous, and longer wings. 



"In autumn and winter the blue of the male is much soiled by 

 umber-brown edges to the feathers, this most conspicuous on the 

 breast, where the blue is sometimes almost concealed; the plumage 

 of the female, too, at this season is different from that of spring, 

 the anterior lower parts being soft isabella-color, much less grayish 

 than in spring." (Hist. N. Am. B.} 



The only claim of this species to a place in the Illinois fauna 

 rests on the single record, by Mr. Nelson (Pr. Essex Inst. viii. 1876, 

 p. 95) of the capture of a specimen opposite Dubuque, Iowa. 



The home of the Arctic or Eocky Mountain Bluebird is the 

 mountainous region of western North America, especially the ranges 

 of the interior, and thence northward through the more elevated 

 portions of British America to a high latitude. As the Californian 

 Bluebird (S. mexicana) is essentially a bird of the lower valleys, so 

 is the present species emphatically a bird of the mountains, its 

 visits to the lower portions of the country being mainly during 

 winter. 



SUBFAMILY MYADESTIN^I. THE SOLITAIRES. 



The birds of this subfamily have usually been placed with the 

 Ampelidae, in a group including also the genera Phainopepla and 



