48 EVOLUTION OF BIRD-SONG 



most extravagant singers. This is obviously the 

 fact. The blackbird, thrush, robin, and blackcap 

 never utter a call-note during song, but they seem 

 to trust only to their more original music. The 

 nightingale often commences its phrases by uttering 

 one of its call-notes. The song of the skylark is 

 often, in early spring, concluded in long notes which 

 resemble the call-note of the young skylark pro- 

 longed. It is obvious that the phrases of inferior 

 singers, such as the greenfinch, creeper, yellow 

 bunting, bullfinch, pied wagtail, hedge-accentor, 

 golden-crested wren, nuthatch, and titmice consist 

 more or less of repetitions of the call-notes of their 

 respective species. 



