OF EASTERN PENNSYLVANIA. 2 I I 



very low key, so as to be almost inaudible at a dis- 

 tance of twenty paces, and which may be re- 

 presented by tze - produced with considerable 

 uniformity of sound. 



The eggs are slate-color, with a tinge of olive, 

 and marked with blotches of dark purplish-brown, 

 with penumbrae of light purple surrounding the 

 darker spots. The average length is .86 of an 

 inch, and the average breadth .65. In shape they 

 vary from oblong-oval to nearly rounded forms. 



Family Vireonidee, Vireos and Grecnlets. 



This family which wa:; former!)' united with the 

 Laniidce which it resembles in the structure of the 

 bill, has structural peculiarities in the feet by which 

 it may be readily discriminated. The Greenlets 

 are peculiar to America, and embrace five or six 

 genera with nearly seventy recorded species, one- 

 sixth of them being probably not genuine. The 

 typical genus l^irco embraces thirty species, 

 specially characteristic of N. America, seven oc- 

 curring in the West Indies and Central America, 

 one being exclusively West Indian, and the rest 

 occupants of South and Central America. 



Vireo olivaccus, Vieill. 



The Red-eyed Vireo is one of the most abundant 

 of our breeding species, in Eastern Pennsylvania. 

 It arrives generally during the last week of April, 

 but, occasionally, as late as the second week of 







May. It is a bold and fearless creature, entering 



