PLATE I. 



A. Dakota sandstone resting on Permian shales. Man's head in line w th 

 contact. Spring creek, six miles north of Washington. 



B. Unconformity of Pleistocene on Permian. Ravine running from It ft 

 to right in Permian shales with thin limestone forming the top cros es 

 a buried gully at right angles to it filled with Pleistocene mater al, 

 which is etching backward. Note the tipping of the limestone i>»to 

 the old gully (undisturbed by recent erosion). About three miles east 

 of Washington. 



