PHILADELPHIA VIREO 351 



foliage, in the very middle of the tree, scarce ten feet below its topmost twigs 

 and fully thirty feet from the ground, a globular object of a light grayish brown 

 color. Holding my glass on it with some difficulty — for I was now actually 

 trembling with excitement — I made it out clearly to be a small, neatly-finished 

 and perfectly new-looking Vireo's nest attached to a short lateral twig of one of 

 the long, upright terminal shoots that formed the crown of the aspen. Looking 

 still more closely I could see the head of the sitting bird and even trace the 

 swelling of his throat and the slight opening of his bill as he uttered his dis- 

 connected notes. Soon after this he left the nest and flying to a neighboring 

 tree alighted on a dead twig where I had a clear view of him and quickly satisfied 

 myself that without question he was a Philadelphia Vireo. 



The next morning the nest was taken, with the three fresh eggs that 

 it contained ; dissection of the female showed that no more eggs would 

 have been laid, Brewster contip.iies : 



The nest was hung, after the usual Vireo fashion, in a fork between two 

 diverging, horizontal twigs. One of these, a lateral branch from the upright 

 shoot already mentioned, is rather more than a quarter of an inch in diameter 

 and evidently formed the chief support, as the other twig is scarce thicker than 

 the flower stem of a buttercup. The nest is firmly bound to both for some dis- 

 tance along its rim. It is much longer than broad, measuring externally 3.20 

 inches in length, 2.75 in width, and 2.65 in depth ; internally 2.00 in length, 

 1.50 in width, and 1.35 in depth. Its walls are more than half an inch thick 

 in iJlaces, its bottom almost a full inch. It appears to be chiefly composed of 

 interwoven or closely compacted shreds of grayish or light brown bark, appar- 

 ently from various species of deciduous trees and shrubs as well as, perhaps, 

 from dried weed stalks. The exterior is beautifully decorated with strips of 

 the thin outer bark of the paper birch, intermingled with a few cottony seed 

 tufts of some native willow still bearing the dehiscent capsules. Most of these 

 materials are firmly held in place by a gossamer-like overwrapping of gray-green 

 shreds of Usnea, but here and there a tuft of willow down or a piece of curled 

 or twisted snow-white bark was left free to flutter in every passing breeze. It 

 would he difficult to imagine anything in the way of external covering for a 

 bird's nest more artistically appropriate and effective. The interior, too, is 

 admirably neat and pretty, for it is lined with the dry, tan-colored needles of 

 the white pine (among which are a very few .slender blades of grass), arranged 

 circularly in deep layers around the sides and bottom of the cup in which the 

 eggs were laid, 



Philipp and Bowdish (1917) found three nests of the Philadelphia 

 vireo in northern New Brunswick in 1916, "The situations where nests 

 were found, as well as where additional birds were observed, were, in 

 every instance, on islands or along the shores of river bottoms, with a 

 growth of willow and alder. 



"The nests found were in slender forks of alder, at a height varying 

 from ten to seventeen and one half feet (the latter actual measure- 

 ment). On June 17, two of these nests held four eggs each, the third 

 five." Their description of the nests is not very different from Mr. 

 Brewster's. 



Dr. Harrison F. Lewis (1921) was fortunate enough to have a pair 

 of Philadelphia vireos build their nest in a young rock maple, within 

 30 feet of the front door of his residence, in the suburbs of the city of 



