66 EVOLUTION OF BIRD-SONG 



In suggesting that some wild birds may derive 

 pleasure from the appearance of their surroundings, 

 I do but put them on a par with the homing 

 pigeon. This bird, in order to return to a former 

 abode, will abandon both mate and young. The 

 male pigeons will " home " better when their mates 

 are sitting than at other periods. It may be as 

 well to remark here that the homeward flight of 

 these pigeons is not directed by any blind instinct, 

 but by sight and memory ; for the birds cannot 

 find their way through thick fog, even from the 

 distance of a few hundred yards. I have excellent 

 authority for these statements. It has been noticed 

 in many birds that the same sites for nests are 

 adopted year after year. 



In this connection may be mentioned the " in- 

 strumental music " which many writers have ob- 

 served, and which may be defined as consisting of 

 sounds other than vocal sounds uttered by birds, as, 

 for instance, the sounds caused by the smiting to- 

 gether of wings, drumming sounds produced by 

 rapid blows of the beak, and similar noises. And 

 in conjunction with this feature we may notice the 

 strange and seemingly purposeless dancing and 

 other antics by which song may be accompanied. 

 Mr. Hudson writes : " There are human dances in 



