44 BIRDSSONGS. 
slight and rather characterless thing, nowise 
remarkable. But coming down Mount Willard 
one day in June, I heard a warbler’s song which 
brought me to a sudden halt. It was new and 
beautiful, — more beautiful, it seemed at the 
moment, than any warbler’s song I had ever 
heard. What could it be? A little patient 
waiting (while the black-flies and mosquitoes 
‘‘came upon me to eat up my flesh’’), and the 
wonderful stranger appeared in full view, — my 
old acquaintance, the yellow-rumped warbler. 
With all this strong tendency on the part of 
birds to vary their music, how is it that there 
is still such a degree of uniformity, so that, as 
we have said, every species may be recognized 
by its notes? Why does every red-eyed vireo 
sing in one way, and every white-eyed vireo in 
another? Who teaches the young chipper to 
trill, and the young linnet to warble? In short, 
how do birds come by their music? Is it alla 
matter of instinct, inherited habit, or do they 
learn it? The answer appears to be that birds 
sing as children talk, by simple imitation. No- 
body imagines that the infant is born with a 
language printed upon his brain. The father 
and mother may never have known a word of 
any tongue except the English, but if the child 
is brought up to hear only Chinese, he will 
infallibly speak that, and nothing else. And 
