OF EASTERN PENNSYLVANIA. 5 



more southern latitudes, for the obvious reason 

 that the three or four days preceding their obser- 

 vance indicated a low degree of temperature; but 

 on the supposition that they were birds which had 

 been left behind in the autumn, when their breth- 

 ren had taken up their southward-bound journey 

 for pleasanter climes, their occurrence need not 

 excite comment or surprise. According to Dr. 

 Brewer many of this species are permanent resi- 

 dents in various parts of the country. 



Nidification commences occasionally during the 

 middle of March, often when there is snow upon 

 the ground, and days before the trees have donned 

 their foliage. Ordinarily, building operations are 

 entered into with considerable vigor about the 

 first of April ; and by the tenth of the month every- 

 thing is in readiness for oviposition. A pair of 

 birds will usually construct a nest in from three to 

 seven days, if working under the most favorable 

 auspices. Two or three days elapse however 

 before oviposition commences; the birds mean- 

 while being engaged in various manoeuvres as if 

 felicitating each other on the successful accomplish- 

 ment of their task. Ordinarily the nest is placed 

 upon the stout limb of an apple-tree. In the selec- 

 tion of a site some birds manifest little judgment so 

 to speak. Before us is a nest which was found 

 in Northumberland County, Pennsylvaina, built in 

 the hole of an upright post. In contour it is nearly 

 elliptical. 



Last spring, our attention was directed to a 



