Devolopment of Animal Intelligence. 179 



similarities and differences, better than any other ; and no one 

 has worked out this view better than Darwin himself in his 

 various works; and so far as the psychic is concerned, especially 

 in his " Descent of Man "; though in this connection Romanes' 

 " Mental Evolution in Animals" and " Mental Evolution in Man" 

 also deserve mention as very admirable and highly scientific 

 works. 



There is, however, another sense in which the term evolution 

 luay be properl}' employed, viz: The unfolding or development 

 of the individual animal from the beginning of its existence to full 

 maturity ; we may speak of the evolution of the chick from the 

 egg ; and in like manner we may follow the evolution of the 

 mind from its first, dim manifestations to its complete develop- 

 ment. 



While the mind of the adult human being had been studied 

 for ages it is only very recently that investigators thought of 

 commencing at the beginning, or in other words, making 

 researches into the nature of the infant mind ; though when one 

 reflects it seems strange that such should have been the case. 



The anatomy of man and the higher animals has been 

 rendered easier of acquirement and its true significance made 

 vastly clearer by comparative anatomy, or the study of one form 

 of animal life as compared with another. Thc-structure of the 

 cat and tiger, related animals, is each better understood if 

 compared. But it is embryology or the study of the develop- 

 ment of animals from their germs that has shed such a flood of 

 light on the structure and relations of the whole animal 

 kingdom. 



The writer being convinced that the same principles apply- 

 to the study of the mental life of animals has for some years 

 been engaged on investigation of the psychic development of 

 animals by a method corresponding to the embryological as 

 applied to physical developement. 



