BLUE-HEADED VIREO 299 



are common, while five- and six-note ones are rather rare. The notes 

 of tlie phrases are sometimes connected by shirring and sometimes by 

 abrupt changes. In phrases of three or more notes both kinds of 

 changes may occur in the same phrase. Such phrases are character- 

 istic of the song, and a help in distinguishing it from other vireos. 

 Such phrases may be written aweeto^ teeaytoay, taweetayo^ etc. 



"On the breeding range in midsummer, this bird sometimes runs all 

 its phrases together, omitting the pauses, producing a warble of 15 or 

 20 notes, the song then suggesting that of the warbling vireo. This 

 song is heard conmionly in the spring migration in April, and occa- 

 sionally in fall in October. 



"On the breeding grounds the period of song lasts till about the third 

 week in August. Then individuals cease singing for a time but revive 

 the song in late August. Definite dates are difficult to determine, how- 

 ever, for some individuals revive the song before others have ceased 

 the main period of singing. Where the species is common one or more 

 birds are likely to be heard in song every day in the summer." 



Francis H. Allen sends me the following notes : "I have heard from 

 both birds of a pair, in June, a faint trumpetlike note uttered with the 

 bill almost closed. Sometimes the note was sounded more emphati- 

 cally with the bill opened a little more. It then had a more strident 

 character. I have also heard the tin-trumpet note in August, some- 

 times with a variant in two syllables, tee-iueh. The chatter of the blue- 

 headed vireo resembles that of the yellow-throated but is not so loud. 



"August 25, 1911 — One feeding in trees in a drizzling rain uttered 

 continually a rather harsh, nasal see-a^ sometimes more distinctly dis- 

 syllable, like see-weep. Once he gave a succession of similar but short 

 notes, like she-she-she-she-she. All the notes were more like the char- 

 acteristic harsh note of the red-eye than the other call-notes I have 

 heard from this species. This may have been a young bird (so far as 

 could be seen in the rain and without a glass, it was not in full plu- 

 mage), but it was well enough grown to take care of itself, and it was 

 alone. 



"One cold afternoon with spits of snow in early May, one of two 

 blue-headed vireos in a hawthorn tree near my house sang sotto voce 

 with snatches of catbirdlike song, a trill, and, later, phrases of the 

 regular song but faint." 



The following note from Mr. Skutch is interesting: "Contrary to 

 prevalent impression, the majority of North American birds that win- 

 ter in Central America may be heard singing here. Most of them 

 rarely sing until the time for their northward departure approaches, 

 yet a few are tuneful even in the midst of the northern winter. Con- 

 spicuous among these are the yellow-throated and blue-headed vireos. 

 With the possible exception of the orchard oriole, the blue-headed 

 vireo is more songful while in Central America than any other of the 



