SAXICOLID.K — THE SAXICULA.S. 



67 



Sialia arctica, swains. 



BOCKT MOUNTAIN BLUEBIBO. 



Eriffhraca (Slolin) nrdtoi. Swains. F. B. A. II, 1831, 209, pi. .\xxix. S'uilia ardkn, 

 Ni TTALL, Man. II, 1*32, 573. — Baiuu, Hirtls N. Am. 1858, •224 ; K.-v. 64. — Sclater, 

 Catiil. 1861, 11, no. 67. — Dresseu, Ibis, 186.5, 478. (T.-xas, winter, very abundant.) 

 — Cooper, Birds (*al. I, 29. S'udui macro^kra, Baird, Stansbury's Kept. 1852, 314 

 (larger race with longer wings). 



Sp. Char. Greenish aztire-blue aliovc and brlow, l)rightest above; the belly and under 

 tail-covcrt.s white; the latter tinjjfed witli 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, G.2o ; wing, 4.30; tail, 3.00. 



(1875.) 



Yonnfj. Male birds are streaked with white, as in S. dalis, on the charaeteristie ground 



of the adult. 



Hab. Central tal)le-lands of North America, east to mouth of Yellowstone. One 

 intlividual collected at Fort Franklin, Great Bear Lake. Not conunon on the Pacific 

 slope ; the only specimens received coming from Simiahmoo, Fort Crook, and Sau Diego. 

 Not recorded as found in Mexico. W. Arizona, Coues. 



As already stated, the blue of tliis species is greener, more smalt-like 

 than in sidlis. Tlie females are distinguished from those of the other 

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



In autumn and winter tlie blue of the male is much soiled by amber- 

 brown edges to the feathers, this most cons})icuous on the breast, where 

 the blue is sometimes almost concealed ; the plumage of the female, too, at 

 this season is difterent from that of spring, the anterior lower parts being 

 soft isabella-color, much less grayish than in spring. 



Habits. This Pduebird belongs chietly to the Central fauna, and occupies 

 a place in the Eastern only l)y its appearance on its borders. It was hrst 

 procured by Sir John Itichardson, at Fort Franklin, in July, 1825. It is 

 abundant throughout the central table-lands of Xortli America, between 

 the Pacific and the moutli of the Yellowstone, from Great Bear Lake to 

 the lower portions of California. In the latter State it is not common. 



^Ir. Xuttall met with this species in the early part of June, northwest of 

 Laramie Fork. The female uttered a low^ complaint when lier nest was 

 ai)proached. This was constructed in a hole in a clay cliff. Another was 

 found in the trunk of a decayed cedar. In one of these the vountr were 

 already liatched. The nest was composed of dried grasses, but in very insig- 

 nificant quantity. ^Ir. Nuttall found them much more shy than the con> 

 mon species, and describes them as feeding in very nearly the same manner. 

 He afterwards found a nest of the same species in a cliff of the Sandy 

 Kiver, a branch of the Colorado. Both parents were feeding their brood. 

 The female was very uneasy at his approach, chiri)ing, and at intervals 

 uttering a plaintive cry. He states tliat the male l)ird has a more plaintive 



