•2 7 4 Brewster, Notes on the Philadelphia Vireo. foct^ 



ably are too slight and inconstant to be easily recognized or safely 

 relied on as a means of identification. In other words, only 

 those who possess critical and highly trained ears can hope to 

 distinguish the Philadelphia Vireo from the Red-eye by its song 

 alone, while even the experts in such matters are likely to be 

 occasionally deceived. 



The bird which we left perched on the dead branch remained 

 there, as I have just said, upwards of ten minutes, basking in the 

 sunshine and pouring out a perfect flood of song. At the end of 

 this period he flew directly back to the nest and on entering it at 

 once resumed the listless, interrupted singing which I have already 

 described. I am nearly sure that he did not again leave it that 

 forenoon, for whenever I revisited it — as I did every fifteen or 

 twenty minutes — I found him still there and still singing. He 

 seemed rather ill at ease, keeping his head in almost constant 

 motion and occasionally turning half around in the nest. Once 

 he stretched his neck well out and down over the rim to seize the 

 loose end of one of its component strands, which he tugged at so 

 violently with his bill as to perceptibly shake the whole structure. 

 Perhaps this was done merely to relieve his evident ennui, or he 

 may have been giving vent to irritation caused by the prolonged 

 absence of his mate, who was not seen at all on this occasion. 



When we took the nest, early the next morning (about six 

 o'clock), the male was again sitting and beguiling himself as 

 before by frequent snatches of his leisurely song. He did not 

 leave the nest until my assistant, Mr. Gilbert, reached and slightly 

 shook the branch to which it was attached, when he flew directly 

 off out of sight through the woods — no doubt in search of his 

 mate, for he returned with her a few minutes later. Both birds 

 came close about Gilbert's head while he was still in the top of 

 the tree, making their low scolding note which so closely resem- 

 bles that of the Warbling Vireo, but the male seemed shy and 

 suspicious and soon departed again. The female was much tamer 

 and showed more concern, remaining in the tree until she was 

 finally shot — just after the nest and eggs had been safely lowered 

 to the ground. On skinning her I found that she would have 

 added no more eggs to the three perfectly fresh ones which were 

 found in the nest. 



