WESTERN BLUEBIRD. 
767. Sicilia mexicana occidentalis. 7 inches. 
Range.—British Columbia to Lower California, along the 
Pacific coast. These familiar birds build in cavities in trees, 
or in bird houses, and make themselves at home near dwell¬ 
ings, especially if in the vicinity of orchards of any kind. 
The note of the western bird has the same familiar warble 
as their eastern relative. They live on small insects and 
caterpillars, and some of the small berries. Their four eggs 
are a pale bluish white (.80 x.60). 
CHESTNUT-BACKED BLUEBIRD. 
767a. Sialia mexicana bairdi. 7 inches. 
Range.—Rocky Mountains from Colorado to Texas (not 
illustrated). 
MOUNTAIN BLUEBIRD. 
768. Sialia currucoides. 7% inches. 
Range.—Rocky Mountain regions from Canada to Mexico. 
Their habits are just the same, eggs averaging slightly larger. 
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