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Puerco and dies out in the Torrejon, true Rodents coming in to take 

 its' place. 



2. The main body of the fauna is composed of primitive types 

 from which sprang the Ungulates on the one hand and the later 

 Creodonts and Carnivores on the other. In the Puerco these two 

 divisions are hardly distinguishable, but in the Torrejon they are 

 clearly separable, although still closely allied. 



3. A few more specialized lines, the Edentata, Amblypoda and 

 Rodents, with a fourth type allied to the Primates, may be separated 

 from the main group. 



A total number of seventy-five species is recognized in the whole 

 fauna. Stuart Weller. 



