344 BULLETIN 20 3, UNITED STATES NATIONAL MUSEUM 



of a rival ; but the intruder in his territory is promptly driven away 

 and he resumes his singing. 



Voice. — Aretas A. Saunders has sent me the following study : "The 

 song of the Blackburnian warbler is one that is usually of two dis- 

 tinct parts, the first a series of notes or 2-note phrases all on one pitch, 

 and the second a faster series, or a trill, on a different pitch. It is very 

 high in pitch, with a thin, wiry quality, rather unmusical, and not 

 loud but penetrating. 



"Of my 34 records, 25 have the second part higher in pitch than the 

 first, while in the other 9 it is lower. I do not think, however, that 

 this means that the higher ending is commoner, for there is reason to 

 think that the difference is geographical. Of 11 records of migrating 

 birds in Connecticut, 10 end in the higher pitch. Of 15 records from 

 breeding birds in the Adirondacks, 13 end in the higher pitch ; but of 

 8 records of breeding birds in Allegany State Park in western New 

 York, only 2 end in the higher pitch, and 6 in the lower. 



"In 20 of the records the first part of the song is of 2-note phrases, 

 but the remainder is of single repeated notes. In 6 records, ending in 

 a higher pitch, the final trill slurs upward in pitch, suggesting the 

 ending of a typical parula song in form. In 10 of the records the 

 second part is much shorter than the first. 



"Songs vary from 1% to 2% seconds, averaging a little longer than 

 those of other species of this genus. The number of notes in songs, 

 excepting those with trills, varies from 7 to 25, and averages 14. 

 Pitch varies from D'''' to F'"', one and a half tones more than an 

 octave. It ranks with the blackpolled and bay-breasted warblers in 

 the very high pitch of its upper notes but shows more variation in 

 pitch than either. 



"The song of this bird ceases earlier in summer than most others. 

 In 14 summers in Allegany Park, the average date of the last song 

 was July 12, the earliest July 4, 1929, and the latest July 22, 1935. I 

 have never heard singing in late summer after the molt." 



Francis H. Allen sends me his impressions as follows: "Like so 

 many of our warblers, the Blackburnian has two song- forms, but both 

 are subject to great individual variation. An extremely high note is 

 almost an invariable characteristic. In one form it is the closing note, 

 and in the other it ends each repeated phrase of a succession that con- 

 stitutes the main part of the song. The first song resembles that of 

 the parula, but ends with this high note, while the main part is less 

 buzzy and more what I might call pebbly in character. The second I 

 have been accustomed to call the chickawee song because of the re- 

 peated phrase which suggests those syllables. At Sherburne, Vt., in 

 June, 1907, 1 found the Blackburnians singing a song that I rendered 

 as chl-ee chi-ee chi-ee chl-ee chip. Another rendering of the same or 



