MENTAL POWERS OP MAN AND LOWER ANIMALS. 193 



But if it be further asked why musical tones in a 

 certain order and rhythm gire man and other animals 

 pleasure, we can no more give the reason than for the 

 pleasantness of certain tastes and smells. That they do 

 give pleasure of some kind to animals we may infer from 

 their being produced during the season of courtship by 

 many insects, spiders, fishes, amphibians, and birds ; for, 

 unless the females were able to appreciate such sounds 

 and were excited or charmed by them, the persevering 

 efforts of the males and the complex structures often 

 possessed by them alone would be useless ; and this it is 

 impossible to believe. 



