IMITATIONS OF THE E IE ME NTS 183 



and when the swish of their wings can be clearly 

 heard many yards below them. It is to be noted 

 that the swift of South Africa " does not pursue and 

 scream like those of Europe" (Layard, op. cit. p. 50), 

 and neither swallow nor martin have either habit or 

 cry. In Canada neither the common swift nor the 

 chimney swift, which closely resembles the British 

 species, cries swee ree, nor any sound approaching that 

 tone ; nor do they pursue each other in the manner 

 of our swift. 



The voices of owls simulate the moaning of the 

 wind in hollow trees, such as these birds frequent. 



Sometimes, when in a wood during a heavy 

 storm, I have noticed that the patter of drops of 

 water on fallen leaves was, in rhythm, not unlike 

 the lit it it cries of the robin. When walking 

 in the forest-park at Vancouver, B.C., in July, I 

 seemed suddenly to be close to a noisy trickling 

 stream, the sound of which was clearly audible 

 through the dense growth of trees. In a few 

 seconds the sounds ceased, but were soon repeated 

 in exactly the same way. I was astonished to find 

 that the sounds were the song of a little bird, 

 apparently a wren. In that mountainous district 

 rushing streams of all sizes are prevalent. It seems 

 to me that some song-birds, such as the robin, wren, 



