64 ANIMAL INDIVIDUALITY [OH. 



shall be appropriate to the circumstances, there must 

 exist a nervous mechanism consisting of various parts, 

 each part capable of being connected up with every 

 other part. To evolve such a mechanism from a 

 homogeneous mass of substance would no doubt be 

 possible, but to evolve it from a collection of cells 

 would be certainly easier, for there at the outset 

 some of the essentials of the finished product the 

 separate parts and their discontinuity would be 

 already given. 



Thus through reaching the second grade of indi- 

 viduality, life has been able to gain both size and 

 brain-power for herself. Arid so it comes to pass 

 that the next steps in her progress have been effected 

 chiefly by the way of internal differentiation. All 

 three ways of change were open to her, and all three 

 have been used in their measure: but the main 

 difficulty, the difficulty of size, has been removed 

 from the path, and the second method can now show 

 its full possibilities. As a matter of fact, the animals 

 of largest size, of greatest intellect, and of best in- 

 stinctive powers are all individuals of the second 

 grade 1 . At the last, however, when the brain and 

 sense-organs are sufficiently developed, life has 

 gained her most elaborate triumphs of individuality 



1 In the vegetable kingdom, things are somewhat different, and 

 the largest plants, the great forest trees, are individuals of a grade 

 higher again than the second. 



