5i8 



A. G. LEONARD 



souri River to within eight or ten miles of Washburn, where they 

 disappear below river level and are replaced by the Fort Union. 

 On the North Fork of the Cannon Ball they extend almost as far 

 west as the Hettinger County line, and on the Heart River they 

 reach to within a few miles of the Stark County line. Along the 

 boundary between North and South Dakota the western border 



Fig. 4. — Bluff of Missouri River near old Fort Rice, showing the lower Lance 

 formation. 



of the formation is not far from Haynes, on the Chicago, Milwaukee 

 and Puget Sound Railroad. 



In passing down the North Fork of the Cannon Ball River 

 from the western edge of Morton County to the junction with the 

 South Fork, and thence down the Cannon Ball River to its mouth, 

 one traverses the entire thickness of the Lance formation from the 

 Fort Union above to the Fox Hills below. About ten miles below 

 the Hettinger County line, in sec. 5, T. 133 N., R. 89 W., the 



