234 POPULAR SCIENCE MONTHLY. 



finely he has elaborated the contrast between the esthetic characters 

 of the two senses. 



What, it will be asked, of the lower animals that have no external 

 ear, or have one that can not be moved? In regard to such, we must 

 carefully distinguish those species which have never possessed the 

 movable ear from those which have lost the power of movement. It 

 is the loss of a faculty once possessed that we are at present more 

 immediately concerned with. Yet, in the case of such animals as the 

 birds, which, though endowed with a highly developed sense of hear- 

 ing, have no external ear, it is interesting to observe that there is 

 remarkable appreciation of music. And this is not merely a response 

 to individual sounds, as the musical appreciation of some animals 

 may be; there seems to be an enjoyment of melody. Browning hap- 

 pily described the thrush as 'wise' because the bird 'sings each song 

 twice over,' and thus shows his ability to 'recapture' 



' The first, fine, careless rapture.' 



It is also to be noticed that many birds can imitate other sounds, 

 even those of the human voice. The repetition may be 'parrot-like,' 

 but it gives evidence of the power of attending to a series of sounds. 



It should be mentioned that the external ear of certain aquatic 

 mammals is atrophied or lost. But as these animals have taken to a 

 different kind of environment, and have been to so remarkable an 

 extent made over, it seems unnecessary in the present investigation to 

 give special consideration to this particular change in their structure. 



The case of the monkeys seems at first to be different. Some of 

 them, the anthropoid apes at least,* have like man lost the power to 

 move the ears, yet they have not, it may be said, the faculty of speech. 

 Have we not, then, the loss without any compensation of the special 

 kind that is here being claimed for man? In considering this ques- 

 tion we must keep in view the psychologist's ignorance of the mental 

 life of the monkey. Notwithstanding all that has been written of 

 the relationship of man to the monkeys, the psychology of these ani- 

 mals is still for the most part a blank. Yet there are some significant 

 data that may in the present case be appealed to. The howling mon- 

 keys, though of low intelligence, find delight in the noise, from which 

 they receive their name. They are gregarious and they howl in com- 

 pany. This noise is not made to drive away enemies; the monkeys 

 gather deliberately for the purpose of making the noise and the leader 

 starts the concert. 



The chattering of monkeys should also be regarded as affording 



* " The more recent ape ancestors, common to men and to the anthropoid 

 apes (gorilla, chimpanzee, etc.) discontinued the habit of moving their ears and 

 hence the motor muscles gradually became rudimentary and useless." Haeckel, 

 'Evolution of Man' (English Translation), Vol. II., pp. 270-271. 



