The Rise of the Mammals 



from a score of faroilies ; and while not one of 

 these families has endured to the present time, 

 yet they were the forerunners of our existing 

 w^olves, cats, deer, and horses. 



These mammals of the Lower Eocene beds 

 were of what is termed generalized types ; that 

 is, they were built on the same general plan. 

 This generalization of structure is shown by the 

 fact that Professor Cope said of certain species 

 that in the absence of the bones of the feet it 

 could not be said whether they were lemurs or 

 insectivores. And later Dr. Matthew decided 

 that some at least were rodents. None of them 

 were very greatly modified for any particular 

 mode of life or kind of food. Such a foot as 

 that of the deer, so clearly fashioned for speed, 

 does not appear among them, nor is any animal 

 to be found with the sharp, retractile claws of 

 a cat. The feet of these creatures were more 

 like those of a tapir, supposing a tapir to have 

 five toes, without any particular adaptation for 

 climbing, running, or striking down prey. Nor 

 did any of these animals have teeth especially 

 modified for cropping grass, though it is easy to 



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