﻿Am. 
  Jour. 
  Sci., 
  Vol. 
  IX, 
  1900. 
  

  

  Plate 
  V. 
  

  

  

  *te 
  

  

  

  Siliceous 
  Calcites 
  from 
  the 
  Bad 
  Lands. 
  South 
  Dakota, 
  x 
  £. 
  

  

  