THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS 263 



hear, taste, pick up and swallow food, drink, run about, 

 etc. 



Its progress is so rapid that in a few days it can lead 

 an independent existence, provided it be protected 

 against cold, wet, etc. 



The chick stands to the pigeon in physical and 

 psychic development, in somewhat the same relation as 

 the rabbit to the cavy or guinea-pig. 



In all these cases, when full maturity is reached, the 

 psychic difference is not great. The rabbit and the 

 cavy are about on the same mental plane, and so are 

 the pigeon and the fowl. 



They all illustrate general laws of development, and 

 the study of these creatures, somewhat low in the 

 vertebrate and psychic scale, seems to me to throw 

 much light on the problems of psychology, viewed not 

 as human psychology alone, but in the broadest possible 

 sense. 



