132 NATURE'S STORY OF THE YEAR 



note, or series of notes, may become itself so all- 

 absorbing as to demand the whole consciousness 

 of the bird, who, in performing it, forgets the why 

 and wherefore of the performance. Let this pro- 

 cess once commence, and certain movements 

 antics performed at first with a definite object, 

 might be gone through at last for themselves 

 alone, the object having become now merely to 

 perform them " (" Bird Watching," p. 93). This 

 gives us a key to the mystery of vocal triumphs in 

 a song-bird which seems not to be actuated by 

 sexual instinct at the time : it is a sound argu- 

 ment for deeming him an artist following his art 

 for its own sake. The varying degrees of origin- 

 ality and skill in the performance, in the different 

 species, can only be detected by very careful and 

 close observation, but the mere duration of the 

 effort is easily ascertained. Even this simple 

 observation may yield a surprising result. We are 

 all familiar with the song of the skylark, and if in 

 spring one of the birds be timed, it will be found 

 to sing, generally, from three to six minutes with- 

 out a break. In June the song is less practised, 

 except in that storm of melody which at dawn fills 



