﻿Plate 24 



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Upper view. Watertown limestone near river at Watertown, showing 

 seven foot tier and the upper portion of the cherty bed beneath. 



Lower view. Trenton limestone in creek bank near Threemile Bay, 

 Clayton quadrangle. A closer and more detailed view of part of the sec- 

 tion shown in plate 25. E. O. Ulrich, photo, 1908 



