EASTERN WARBLING VIREO 369 



same length. A common form is made up of one long note followed 

 by two short ones, and wlien this is repeated several times it is like 

 dactylic feet in poetry. It is common for the song to end on a high 

 note." 



In the summer of 1912 a bird that was breeding on Lexington 

 Common, within hearing from my windows, showed a marked depar- 

 ture from the norm.al song. My notes say : "He often utters a part 

 of his song in a squeaky voice with no whistled quality whatever, the 

 tone becoming so high that it contains a sibilant sound. Sometimes 

 he changes to the squeak in the middle of the song, returning to the 

 whistle before the end ; sometimes he ends with the squeak," Strange 

 to say, later in the same year I heard a similar song from another 

 warbling vireo breeding 5 miles from Lexington. This variation, 

 however, must be rare, for I have not heard it since, although I have 

 heard the red-eyed vireo sing in this manner. 



The bird often sings until well into September: Mr. Bent has 

 heard it singing daily from August 31 to September 13, inclusive, 

 and my records for 10 years average August 27, the latest being 

 September 18, 1910. 



The warbling vireo has two common minor notes; one the sound 

 that resembles the sharp clipping of garden shears, mentioned under 

 "Young," and a complaint note, corresponding, apparently, to the 

 quee of the redeye, but with no downward inflection. It is a hard, 

 tense snarl, with sometimes a slight upward inflection, easily recog- 

 nized as a diagnostic note of the species. 



Dr. Jonathan Dwight, Jr. (1897) , makes an interesting comment on 

 this latter note. Speaking of a similar note of the Philadelphia vireo, 

 he says : "It does not resemble the corresponding complaint note of 

 olwaceus, but is almost exactly like the aggressive myci of gilvus, which 

 has a suggestion of the katydid about it." 



Til ford Moore says in his notes: "Today I saw one singing in 

 flight; he finished his song just after alighting but sang three-quarters 

 of it in flight." 



Field marks. — The warbling vireo has no mark in its plumage that 

 enables us to identify it at a glance as a species. It has no wing bars, 

 no eye ring, no distinctive lines on the head, like some of the other 

 vireos : it is merely a gray-green little bird, but, from the shape of its 

 bill and its manner in moving about, clearly a vireo. So we have to 

 come to an identification by elimination, by the process of reductio 

 ad absurdum. 



Yet, before long, when we have seen the bird time and time again, 

 it begins to take on an individuality of its own, as all birds do when 

 we learn to know them well, and we recognize it, not, as we recognize 

 many birds, by some peculiarity of plumage, not even because it lacks 

 any distinctive marks, but because it suggests the definite personality 



