OF EASTERN PENNSYLVANIA. 299 



The nests were built exteriorly of grasses and 

 dry bark loosely aggregated, and warmly lined 

 with feathers; and when placed upon the ground 

 were generally hidden within a tuft of grass. The 

 complement of eggs varies; the usual number 

 being four or five, while some nests contain occa- 

 sionally, six, and others, seven. The duty of incu- 

 bation apparently devolves upon the female, her 

 partner as in the case with others which we have 

 mentioned, beino- seldom seen in the immediate 



o 



vicinity. 



The eggs, according to Dr. Brewer, are a light 

 green, freckled with fine foxy-brown markings 

 which are uniformly distributed, but in such a 

 manner as to leave the ground distinctly visible. 

 They measure .85 of an inch in length and .65 in 

 breadth, and are much larger than the eggs of any 

 other species of Spizclla. 



Spizella socialis, Baird. 



The Chipping Sparrow so familiar to all, is one . 

 of our most abundant migrants. Its presence is 

 unnoticed long after the Song and Field Sparrows 

 have made the fields and woods vocal with their 

 melodies. It arrives in our midst during the last 

 week of April. Unlike its near relative Spizclla 

 pusilla, it prefers occupied and cultivated grounds, 

 rather than waste fields and the borders of thickets. 

 It is a cheerful and active little creature, and com- 

 mends itself to our favor by its remarkable tame^ 

 ness and sociability. It is a frequent visitor to , 



