BLUEBIRD
766. Sialia sialis. 7 inches
These beautiful, gentle and well-known birds spend the winter in the southern parts of the United States and north to the snow line; some more hardy than the rest are found throughout the winter in southern New England.
Call.—A short sweet warble; song, a continued warbling.
Nest.—In holes in trees, particularly in orchards, in bird boxes or crannies about the buildings. The bottom of the cavity is lined with grasses for the reception of the four or five pale bluish eggs, which measure .84 × .62.
Range.—Eastern United States, breeding from the Gulf to New Brunswick and Manitoba; winters chiefly in the southern parts of the United States. 766a. Azure Bluebird (azurea) is found in the mountains of eastern Mexico and north casually to southern Arizona. It is paler both above and below than our eastern bird.