BIRDS OF MINNESOTA. 365 



VIREO GILVUS (ViEiLLOT). (627.) 

 WARBLING VIREO. 



Excepting the Red-eyed, this is the most abundantly repre- 

 sented species of the genus. It arrives about the 10th of May, 

 remaining until late in September, and occasionally October. 



Its habits in .common with the others of its genus, are such 

 that its presence might escape the attention of the casual ob- 

 server but for its beautiful warblings which there is no mistak- 

 ing for any other. It is emphatically the domestic representa- 

 tive of the vireos, notably preferring the poplars in which to 

 build its nest, and rear its young. Rather than occupy the 

 other common trees in the vicinity of dwellings, it will go to 

 the small groves and borders of the forest, but is almost never 

 found in the denser timber. It is not a whit behind the Red- 

 eyed Vireo as an insecticide, leaving nothing of the kind living 

 on the trees it specially inhabits and few anywhere very 

 near. 



Its song is liquid, fluent, exhilarating, undulating, smooth 

 and melodious as a flute, and remarkably prolonged for a bird 

 of its size and genus. The nearest approximation to any de- 

 scription which I can conceive of is a fairly strong, sweet trill, 

 modulated into symmetrical undulations, with just interruptions 

 enough to keep the vocal cords always up to their best. It 

 sings while skipping from twig to twig amongst the topmost 

 branches of the tree in which its form remains essentially in- 

 visible while searching for its special food. The nest is sus- 

 pended in a very delicate manner from small horizontal twigs 

 where they unite with a larger perpendicular one, around which 

 fibres of bark are wound with much skill to amply secure it. 

 It consists of fine strips of bark and fibres of wood, dried grass, 

 vegetable down, shreds of larval cocoons and fragments of 

 wasp's nests, and is lined with fine bark. It is usually about 

 two inches in depth, but occasionally much more shallow. The 

 characteristics of the vireos are in nothing more marked than 

 in the slim, white eggs sparingly spotted with reddish-black 

 at the larger end. They are generally limited to five in num- 

 ber, and are laid about the first week in June. The nest is 

 placed usually well toward the top of the tree, however tall it 

 may be. 



SPECIFIC CHARACTERS. 



Third, fourth and fifth quills nearly equal; second and sixth 

 usually about equal, and about . 25 of an inch shorter than the 

 third; exposed portion of the spurious quill about one-fourth 



