TERTIARY SECTIONS 



17 



GREAT PLAINS SECTION 



PLEISTOCENE 



PLIOCENE 



OREGON,, SECTION^ 



=. ^Efmvs*_f=-b--^E MIOCENE 





~ 



JMERYGQCHCERUS 



L EPTA UCTJ EN I AX- -_ 



v_ 



QREODCXEt: 



DICERATHERlUr* 



OLIGOCENE 



TITAMOTHERIUM- 



UTAH SECTION 



_ QlP-l> 



WYOMING SECTION 



OOOOQOOOOOOOO O O O O O OOOOO 



(joooooaoooooooo ooooooo 



OOOOOOOOOOOOOO O O OOOOO 



EOCENE 



trMAT6THERIUM 



,r 



NEW MEXICO SECTION 



MONTANA SECTION'-': 



. ....... . .. . 



CRETACEOUS 



Fio. 2d. Diagram showing the chronological and stratigraphic succession of the Cretaceous, 

 Tertiaiy and Pleistocene formations of the western states, in which fossil mammals are found. 



B 



