Proceedings Am. Philosoph. Soc. Vol. XLI. 



Plate IX 





Fig. I. Titanotherium beds topography as exposed in Indian Creek, Big 

 Badlands. Note the rounded character of the hills. The Sheep Mountain sec- 

 tion of Oreodon and Leptauchenia beds is seen in the distance to the left. 





Fig. 2. Section of the Oreodon beds in Corral Draw, Big Badlands. The 

 upper nodular level is marked (*), and the lower zone of rusty nodules or 

 the red layer (**). Photo from the collection of the late S. W. Williston. 



