Animals Before Man 



tlie upper part of the Cretaceous beds, and is 

 looked upon as the descendant of another turtle 

 found in the lower portion of the same system. 



The largest living turtle, Sphargis, compared with the skull of 

 the fossil Archelon. The original skull is 3 feet long. (After 

 Wieland.) 



For it must not be forgotten that the interval 

 of time between the lower and upper part of a 

 series of rocks is veiy great ; so that while the 

 general character of the life in the system is 



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