The Life of Yesterday 



by man, for bad this been the case we should 

 have had plenty of proof of the existence of 

 the two at the same time. As for natural 

 causes, the animal ranged over so wide an ex- 

 tent of territory, that while drought, or flood, 

 or cold might have wrought local destruction, 

 somewhere else it would have found peace and 

 plenty. The old theory of sudden change of 

 climate can scarcely be considered, for there is 

 no evidence that any such change took place, 

 and even had it occurred, more creatures than 

 the mastodon would have been annihilated. 

 When the great ice-sheet overlaid the northern 

 and eastern part of our continent, and the cli- 

 mate was such that the walrus disported him- 

 self along the coast of Virginia, the mastodon 

 could have survived in Florida, Texas, and 

 Louisiana, where its remains abound. That 

 he did survive somewhere is evident from 

 the fact that after the final retreat of the ice 

 the animal spread north even into Canada, 

 apparently making its last stand in a belt 

 of country running from Michigan to New 

 York. 



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