How the History of the Past Js Head 



still remaining to throw some light on those 

 that have passed away. 



From the animals and plants we are able to 

 tell what the climate was at different periods ; 

 for when, in the rocks of Wyoming, for exam- 

 ple, we find fossil palms resembling those now 

 living in the tropics, or a breadfruit-tree turns 

 up in California, we naturally infer that the 

 climate of that part of the world was very 

 much wanner then than now. So the former 

 presence in Greenland of forest trees similar 

 to those now growing in New York indi- 

 cates that the climate of the entire globe 

 was once milder. And if remains of great 

 reptiles are found associated with plants, these 

 inferences are strengthened, for the reptiles 

 of to-day have their headquarters in warm 

 countries, and large forms never cross the line 

 of frost. 



On the other hand, the bones of reindeer in 

 southern Europe, and those of musk-oxen in 

 Kentucky, tell of a time when these places were 

 far colder than now, and that their tale is true 

 we know from the testimony left by the great 



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