MORE WONDERS FROM NATURE'S BOOK 



After those great forests had done their work by 

 clearing the atmosphere of its burden of carbon, a 

 great change came. The sun began to shine through 

 the clouds; not peep through with a soft glimmer- 

 ing light, but shine directly through, with rays so 

 bright that they would make a shadow. 



Then all the living things upon the whole world 

 changed. Some kinds of the giant trees died out and 

 were seen no more. Other kinds became smaller and 

 smaller from age to age until they dwindled down to 

 the size of our queer little horse-tail rush and our 

 ground-pine. New trees of a different kind com- 

 menced to grow on the higher ground, and the sun 

 caused them to flourish and to spread. Among these 

 were the conifers or cone-bearers, the first of the 

 group of trees to which our pines and hemlocks 

 belong. 



The animal life, too, was changing, for the air was 

 now fit to breathe. Out of the water came the queer- 

 est-looking creatures that you could ever imagine. 

 They were the amphibians; that is, animals that 

 could live either on the land or in the water. You 

 remember how the little tadpoles, after they are 

 hatched from the eggs, live in the water almost like 

 fishes, and how, when* their legs grow and their tails 

 shrink away, they leave the water and hop out on the 



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