THE WARBLING VIREO. 249 



the most critical ear will, in many cases, find great difficulty 

 in distinguishing between the two. The notes of philadelphicus 

 are generally pitched a little higher in the scale, while many 

 of the utterances are feebler, and the whole strain is a trifle 

 more disconnected. But these differences are of a very 

 subtle character, and, like most comparative ones, they are 

 not to be depended upon unless the two species can be heard 

 together. The Philadelphia Vireo has, however, one note 

 which seems to be peculiarly its own, a very abrupt, double- 

 syllabled utterance, with a rising inflection, which comes in 

 with the general song at irregular but not infrequent inter- 

 vals." 



Similarity of appearance to the Vireos generally, and 

 close resemblance in vocal habit to the Red-eyed Vireo, 

 have no doubt caused the species under review hitherto to 

 elude notice. Now that the points of discrimination have 

 been so well brought out by Mr. Brewster, it may, perhaps, 

 be found generally and commonly distributed in Eastern 

 North America. 



In the deep forests, or .possibly in some thickly-shaded 

 yard, already in the latter part of April, I may meet the 

 Yellow-throated Vireo (Vireo flavifrons}. Well nigh six 

 inches long, yellowish-green above, wings and tail deep 

 dusky, the feathers edged with white or yellowish, wing- 

 bars white; throat, breast and eye-lids bright yellow, the 

 remaining under parts white, it is the brightest of its genus. 

 It keeps well up in the tops of the trees, diligently glean- 

 ing as it sings, vireo, vire-ee, wee-ree, etc., in tones rather 

 shrill for a Vireo, and not nearly so finely modulated and 

 fluent as those of its relative, the Red-eye, but greatly 

 resembling them. Breeding "from Maryland and Virginia 

 northward" (Coues), its nest, some 5 to 15 feet from the 

 ground, is not uncommon in this locality. 



