D. VIRENS : BLACK-THROATED GREEN WARBLER. 125 



land pineries is accurate. Entering this country late 

 in April, certainly by the opening of the following 

 month, they spread at large, leaving representatives 

 all the way, and some proceed northward beyond our 

 limits. Family cares concluded, the return movement 

 begins early in September, or even during August ; 

 some may still be seen in Massachusetts in October, 

 and all do not withdraw from the Connecticut Valley 



FIG. 31. BLACK-THROATED GREEN WARBLER. (Natural size.) 



until the latter part of this month. They are very well- 

 known birds, so numerous are they, and so easy to 

 identify by their conspicuous colors, active habits, and 

 energetic notes, repeated almost incessantly during the 

 nuptial period. One can hardly enter a piece of pine- 

 woods during the summer without having his attention 

 soon attracted by their quaint notes, and he will not be 

 long in discovering from what birds the sounds proceed, 



