114 ANIMAL INDIVIDUALITY [OH. 



in just such an environment; but in the outer world 

 the conditions are rarely narrow and rigorous enough 

 to call forth such adaptations 1 . 



It was the other method, aggregation of similar 

 units and subsequent division of labour among them, 

 that opened to life the full resources of the second 

 grade of individuality. In some colony like Volvox 

 there once lay hidden the secret of the body and 

 mind of man. 



CHAPTER Y 



THE LATER PROGRESS OF INDIVIDUALITY 



" It is provided in the essence of things that from any fruition of 

 success, 110 matter what, shall come forth something to make a 

 greater struggle necessary." WALT WHITMAN. 



EVERY human being who has passed through the 

 moral struggle will testify to the truth of these, 

 Walt Whitman's words, in their own experience : 

 the biologist will witness that they symbolize as 

 real a truth in the history of life. Life can never 

 be in equilibrium. Given the two well-established 

 facts, that living substance can vary, and that living 



1 To mention two examples, there is the strobila with its ephyrae, 

 and the Syllids produciug their special (epitokous) male and female 

 forms bv division. 



