BLUE BIRD. 6g5 



feathers white for more than half their length. Broad lines on sides of head, black. Female and y oung 

 more grayish, with markings less distinct. 



OBSERVATIONS. 



Known by the gray back, white under parts and black wing and tail. An Old World species, occurring 

 also in Greenland and Labrador. 



DIMENSIONS. 



Length, from 6.65 to 6.75 ; stretch, 11.50 to 12..50 ; wing, 3.65 to 3.75; bill, .50 to .60; tarsus, 95 

 to 1.00. 



DESCRIPTION OF NESTS AND EGGS. 

 Nests, placed in holes in the ground or in rocks, composed of weeds, grass, etc. Eggs, four, five and 

 seven in number, rounded oval in form, grayish blue in color, without spots. Dimensions, .55 by .80 to .60 

 by .85. 



FAMILY SAXICOLIDAE. THE BLUE BIRDS ETC. 



Marginal indentations of sternum exceeding in dejith the height of the keel, but the width of the ster- 

 num is more than half the length of the keel. This family differs from that of Turdidae in having the 

 sternum wider in proportion to its length. The tail is also square and emarginate, while in Turdidae it is 

 always rounded. 



GENUS. SIALIA. THE BLUE BIRDS. 



Gen. Ch. Primaries, ten. Wings, pointed. Tail, shorter than the wing, square and somewhat emar- 

 ginate. Predominating color above, blue. Sexes not similar. 



SIALIA SIALIS. 

 Blue Bird. 



Sialia sialis Baird, Birds of North America, 1858, 222. 



DESCRIPTION. 



Sp. Cu. Form, somewhat robust. Bill, not very slender ; gently curved at the tip, and slightly notched. 

 Tongue, acuminate, bifid, and fringed with rather coarse cilia at the end. Sternum, quite strongly built. 

 Color. Adult male in spring. Above, uniform dark blue, with the tips of the primaries, secondaries, and 

 inner edges of the tertiaries, dark brown. The ends of the tertiaries, secondaries, primaries and tail, are 

 narrowly edged with white. Lores and ear coverts dusky. Chin and sides of the throat, blue ; this color 

 sometimes extends over the entire throat, and, in some specimens, even reaches the upper part of the breast. 

 Breast, sides and flanks, rich chestnut brown, with tlie al:ulomen dirty white. The under tail coverts are 

 pale blue. Tibiae, dusky. Under wing coverts, axillaries, and under portion of the tail, blue, of a lighter 

 shade than the upper parts. The remainder of under side of wings, glaucous. In autumn there is a reddish 

 suffusion over the upper surface, and less dusky about the sides of the head. Adult female in spring. 

 Above, pale blue, becoming brighter on the ^yings and upper side of the tail. There is a reddish wash over 

 the middle of the back, and on the shoulders The ends of the wings are colored as in the male. Sides of 

 the head, dusky. Chin, throat, abdomen and under tail coverts, dirty white ; remainder of under portions 

 of the body, chestnut, as in the male, but paler. Axillaries and under wing coverts, bluisli white. Tibiae, 

 dusky. In autumn the chin and throat are like the breast ; the white of the abdomen and under tail coverts 

 is purer. Young male, differs from the adult in having a whitish wash over the breast. There is also a 

 more rufous suffusion above. The tertiaries are edged with reddish and white, and the entire colors are 

 paler. Young female, darker above than the adult, with tlie tertiaries edged with rufuus and white. A red- 

 dish wash extends over the head and b:ick. The chin and throat are like the breast. The white of the 



