12 Bird-Song : and New Zealand Song Birds 
towards a female, singing* a charming whisper-song—and the 
female sought refuge in flight. When the cicadas are singing 
in their thousands, never once has a female been seen to 
approach the joyous males; neither has a female thrush ever 
been seen to approach the male singing by the hour on the 
tree-top; nor has the song, either of cicada or thrush, lessened 
in consequence, either in volume or charm. If it be said that 
the female shows subsequently that she acknowledged the 
attraction, how is that known? 
Birds appear to sing in emulation; and whilst emulation may 
indirectly be connected with courtship, birds will sing in emula¬ 
tion when courtship has ended successfully in the securing of 
a mate—when it may, indeed, be said that emulation has passed 
in a natural course to exultation. Bolton (BH, vol. 1, p. 15) 
writes of the blackbird, “when two are singing at the same 
time within hearing of each other they will contend in song 
like the nightingale, each keeping silence alternately till the 
other has repeated his song. ’ 7 Birds are often matched in song 
by fanciers, and will at times, at such contests, sing themselves 
to death; and some naturalists believe that singing is almost 
exclusively the effect of rivalry and emulation (DD, pp. 369- 
70). The editor of White’s Selborne remarks (WS, p. 123) in 
a note that the song of the swallow exhibits no appearance of 
emulation, but that “it seems to proceed from feelings of 
happiness and complacency, which cannot be mistaken. I like 
to watch it darting now and then to its nest, and uttering that 
little note of love which is responded to by the female whilst 
she is performing her task of incubation . . On this 
point, how is it known that the brooding female pays special 
regard to the song of her mate ? How is it known that she 
does not pay equal regard to the song of every bird singing 
within hearing ? There is always the human analogy; and the 
human analogy, if we be honest, will lead us to most varving 
and contradictory conclusions. 
Again, is it sexual desire, or emulation, or pleasure that 
induces one bird to imitate the notes of another—more, to 
incorporate the songs of others into its own, with characteristic 
