306 LIFE-HISTORIES OF BIRDS 



a slight downward tendency, so as to give a slight concavity 

 at the top. Occasionally, they are laid quite horizontally, 

 until within one inch of the summit, when the margin is 

 made to slope by giving the requisite inclination to the com- 

 posing materials. The diameter at the base is four inches, 

 which gradually increases to about four and a half at the top. 

 The height is two and a half inches, and the depth of the 

 cavity so very shallow, that the tops of the eggs actually ex- 

 tend above the level of the outside margin. Sometimes, 

 when the branch is violently shaken by the wind, the eggs 

 and young are jostled out, and fall upon the ground. But to 

 obviate as much as possible this disadvantage, a tree is fre- 

 quently chosen on the south slope of a declivity, or in a place 

 carefully protected by natural, or artificial surroundings. 

 The nest that is placed upon the ground, does not differ mate- 

 rially from the foregoing in size, nor in the manner of its 

 construction, but in the elements of its composition. As a 

 ground-work, it consists of the stems of Phleum pratense 

 and wheat stubble, which are rather closely piled together ; 

 it is lined with fine grass-stems, and, occasionally, with blades 

 of the same. 



Oviposition occurs on the day following the completion 

 of the nest. The eggs to the number of two are laid on 

 consecutive days. Incubation ordinarily commences on the 

 5th day of May, and continues until the I9th, thus making 

 the period of incubation fourteen days. The female per- 

 forms this duty exclusively. While she is thus engaged, 

 the male supplies her with food, but is seldom seen on the 

 same tree when not thus employed. He is, however, close- 

 by, and responds to the call of his mate with considerable 

 alacrity. When the nest is approached, the female vacates 

 it immediately, but lingers in the same tree, or on a stump 

 or fence close-by, and quietly, but sadly, contemplates its 

 destruction by sacrilegious hands, without so . much as a 

 murmur of complaint. The male is more timid than his 

 partner, and surveys the demolition from a wary distance. 



