Animals Before Man 



land, and has thus remained unaffected by the 

 changes that have taken place elsewhere. 



The story of Cretaceous mammals is as 

 brief and unsatisfactory as that of the Jurassic, 

 and, like that, is interpreted from teeth, jaws, 

 and fragmentary bones. A few more species 

 are known, but all from this continent are 

 small, and the majority belong to the order Mul- 

 tituberculata, some representatives of which en- 

 dured even into the Eocene. So far as mam- 

 mals are concerned, the Cretaceous period is 

 like the Jurassic, and until the disappearance 

 of the dinosaurs mammals made practically no 

 progress. Not that there was any competition 

 between the two, but that conditions favorable 

 to one seem to have, been unfavorable to the 

 development of the other. 



Most of the specimens come from the Lara- 

 mie beds of Converse County, Wyo. the same 

 beds that have yielded the bones of the great 

 dinosaur Thespesius, and his still larger asso- 

 ciate, Triceratops. 



It may be of interest to know how the 

 small, scattered teeth from which the early 



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