66 NORTH AMEKICAX lURDS. 



tliatof thcKasteni species. He describes it as a curious pertnrmauce, sound- 

 in*^ as if two hirds were siii«qii<' at once and in difterent kevs. 



Many of this sj>ecies remain in Wasliington Territory during tlie winter, 

 wliere Dr. Cooper met with them in December. Tliey associated in flocks, 

 freipiented roadsides and fences, and led upon insects and berries. 



Dr. Gambel found this species throughout the liocky Mountains, and always 

 in company with the Siaiia ardira, being by tar the more abundant sjKicies. 



Dr. Kemierly mentions finding this species very abundant during his 

 march up tlie llio (Tiiinde. Through the months of Xoveml)er, December, 

 and January they were always to be seen in large flocks near small streams. 



The Western lUuebird constructs a nept usually of very loose materials, 

 consistiuLj: chiefly of fine drv grasses. These are not woven into an elaborate 

 nest, but are simply used to line tlie hollows in which the eggs are deposited. 

 Near San Francisco Mr. Hepburn found a pair making use of the nest of the 

 Hirundo lunifrons. On another occasion the Bluebirds had not only taken 

 possession of the nest of this swallow, but actually covered up two fresh eggs 

 with a lining of dry grasses, and laid her own above them. 



Th» 'ggs, usually four in number, are of uniform pale blue of a slightly 

 deeper shade than that of the S. slalis. They measure .87 of an inch in 

 length by .09 in breadth. 



Dr. Cooper's subsecpient observations of this species in California enabled 

 him to add to liis account of it in his report on the birds of that State. He 

 found it al)undant in all the wooded districts, except high in the mountains, 

 and thinks they reside through the summer even in the hot valley of the Eio 

 Grande, where he found them prejmring a nest in February. On the coast 

 they are numerous as far north as the -tDth parallel. He found a nest under 

 the porch of a dwelling-house at Santa Barbara, showing that, like our Eastern 

 species, they only need a little encouragement to l^ecome half domesticated. 

 They raise two broods in a season, the first being Jiatched early in April. 



At Santa Cruz he found them even more conflding than the Eastern species, 

 building tlieir nests even in the noisiest streets. One brood came every day 

 during the grape season, at about noon, to pick up grape-skins thrown out 

 by his door, and was delightfully tame, sitting fearlessly within a few feet of 

 the open window. 



In regard to their sf)ng Mr. Kidgway states that he did not hear, even 

 during the ]>airing season, any note approaching in sweetness, or indeed 

 similar to, the joyous spring warble which justly renders our Eastern Blue- 

 bird (*S^ sialh) so universal a favorite. 



The two Western species of Siaiia, though associating during tlie winter 

 in the region along the eastern base of tlie Sierra XeNaila, are seldom seen 

 together during the breeding-season ; the S. urvtka returning to the liigher 

 portions of the thinly wooded desert mountains, while the aS'. me^vicana re- 

 mains in the lower districts, either among the cott(mwoods of tlie river 

 valleys or among the pines around the foot-hills of the Sierra. 



