TIME AND CHANGE 



perience in organization, at last made the problem 

 of the origin of man easier to solve? 



One fancies every living thing as not only re- 

 turning its mineral elements to the soil, but as in 

 some subtle way leaving its vital forces also, and 

 thus contributing to the impalpable, invisible store- 

 house of vital energy of the globe. 



At first among the mammalian tribes there was 

 much muscle and little brains. But in the middle 

 Tertiary the mammal brain began suddenly to en- 

 large, so that in our time the brain of the horse is 

 more than eight times the size of the brain of his 

 progenitor, the dinoceras of Eocene times. 



Nature seems to have experimented with brains 

 and nerve ganglia, as she has with so many other 

 things. The huge reptilian creatures of Mesozoic 

 time — the various dinosaurs — had ridiculously 

 small heads and brains, but they had what might 

 be called supplementary brains well toward the 

 other end of the body, — great nervous masses near 

 the sacrum, many times the size of the ostensible 

 brain, which no doubt performed certain brain func- 

 tions. But the principle of centralization was at 

 work, and when in later time we reach the higher 

 mammalian forms, we find these outlying nervous 

 masses called in, so to speak, and concentrated in 

 the head. 



Nature has tried the big, the gigantic, over and 

 over, and then abandoned it. In Carboniferous 



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