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TITANOTHERES OF ANCIENT WYOMING, DAKOTA, AND NEBRASKA 



Geologic succession of Oligocene titanotheres in the Ohadron formation 



[Levels (above Pierre shale except as otherwise indicated) mostly taken from J. B. Hatcher's field records of 1886, 1887, 1888. Genera and species of fossils determined by 



H. r. Osborn and W. K. Gregory] 



