358 BULLETIN 19 7, UNITED STATES NATIONAL MUSEUM 



I would merely emphasize the fact that it is the essence of the song and enters 

 into it at as i-egular intervals as any of the other notes. It is a liquid note, be- 

 ginning the song and occupying about three fifths of a second for the two syl- 

 lables of which it is composed, on both of which considerable emphasis is laid. 

 There seems to be a slight trill or ripple between the syllables when heard close 

 at hand and the inflection rises slightly on the latter. A pause follows, ap- 

 proximating one and two fifths seconds, and the first note is again repeated, less 

 forcibly and slightly varied. Again the pause ensues, and now it is followed by 

 a triple note, not interrogatory and indistinguishable from one of V. oUvaceus. 

 Again the pause, this time followed by a repetition of the triple note, slightly 

 varied so as to lose some of its sibilance, and after the customary pause of one 

 and two fifths seconds, the song is repeated from the beginning, nearly eight 

 seconds having elapsed in completing one cycle. The four notes may be sug- 

 gested by the syllables chur-r'we, chur-we, pst'-l-rc, psr'-r-re. * * * 



The speed at which the song flows is an interesting factor and is remarkably 

 uniform for each individual songster, — in fact, I could almost identify certain 

 Philadelphias and Red-eyes by timing their songs. V. pJiiladeJphicus sings at 

 the rate of from twenty-two to thirty-six notes a minute, averaging a trifle over 

 twenty-six, while V. olivaccus rattles on at the rate of from fifty to seventy, 

 their song rate averaging a trifle over lifty-nine. * * * 



The male Vireos are in full voice during June, but toward the end of the 

 month the song period rapidly wanes, and after the first days of July their notes 

 are not very often hoard save as a subdued warble at rare intervals. 



Also referring to Mr. Brewster's "double-syllabled utterance," 

 Philipp and Bowdish (1917) write : "In our experience with the birds, 

 this distinctive song absolutely predominated with the general impres- 

 sion of a song quite distinctive from that of the Red-eye, or, in fact, 

 of any other Vireo we had heard. 



"These birds have the common scolding note characteristic of Vireos, 

 but, in addition, they gave voice to several rather musical, but appar- 

 ently protesting notes. In one instance, the female sung a subdued 

 but musical reply to the song of her mate who was at a little distance 

 from the nest on which she sat." 



Dr. Lewis (1921) also says that it is certain that the female can 

 sing, and that her song is sometimes, at least, made up of notes differing 

 from any heard from the male. "The only songs which I know with 

 certainty were uttered by the female are two loud 'Doodle-ee?'s,' a few 

 very low notes, and the song which she sang just after laying her last 

 Qgg on June 18. This latter song was very sweet, clear, and simple, 

 and was sung slowly for eight minutes in a low voice. It consisted of 

 a variety of notes, such as 'HMlit; ee-do-it; way-wer; ee-chew-ee; 

 doo-we?; hiiUit-whew !', uttered over and over in a different order 

 each time. The effect was charming." 



He seems to differ from Dr. Dwight in the rapidity of the song, for 

 he says : "On June 21 1 counted for five minutes the song utterances of 

 a bird which was singing this song [the one mentioned below] among 

 the oaks, and found the number of utterances per minute to be seven, 

 seven, nine, eleven, and six, respectively. A similar count for one 



