FAMILY Vireonid2. 
disappear before one can adjust the opera-glass—it is he! 
But there can be no doubt about the identification of the 
slippery little fellow if one will depend upon the ear 
rather than the eye, for the song is a continuous warble 
exclusively his own, although resembling in its general 
free character that of the Purple Finch. Different 
writers describe his voice as a rambling soprano; which 
is all well enough in its way, but generalities, as a rule, 
are unsatisfactory and misleading, and such a descrip- 
tion tells less than half the truth. There is more in the 
Warbling Vireo’s song than at first would appear. In 
construction it is a smooth, continuous flow of about 
nine or more notes of equal value. There is no other 
Vireo that sings thisway. Again, the Warbling Vireo’s 
attempt at music does not resemble a song as much as it 
does a bit of a fantasia, caprice, or the somewhat rapid 
movement of asonata. When the bird begins he runs 
on until he has finished, without break, pause, or any 
unevenness whatever. Here isa record from Saxton’s 
River, Vt., taken May 23, 1901: 
Twice De PK aS e 
mp res. Fe 
So little is there of variation in the character of the 
song, that a sufficient proof of that fact is found in the 
record I made in Cambridge, Linnean Street, two years 
earlier—May 21, 1899. 
“ \MB  \cres. nn ae 
Ns 
This song is constructively identical with the record 
taken in Vermont. One needs to bear several points in 
mind in learning the character of the Warbling Vireo’s 
music. Itisalmost entirely without definite pitch—that 
is, the bird does not seem to sing on any particular key 
(Ican not too emphatically state that fact); furthermore, 
154 
