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  U 
  

  

  GEOLOGICAL 
  SURVEY 
  OF 
  ILLINOIS, 
  

  

  A. 
  H. 
  WOETHEN, 
  Director. 
  

  

  ^c.o 
  

  

  <*» 
  

  

  VOLUME 
  VII. 
  

  

  GEOLOGY 
  i 
  PALEONTOLOGY 
  

  

  GEOLOGY, 
  

  

  By 
  A. 
  H. 
  WORTHEN. 
  

  

  PALEONTOLOGY, 
  

  

  £/7 
  felt? 
  

  

  By 
  A. 
  H. 
  WORTHED, 
  ORESTES 
  St. 
  JOHN 
  and 
  S. 
  A. 
  MILLER, 
  

  

  WITH 
  ADDENDA 
  

  

  BY 
  CHARLES 
  WACHSMUTH 
  AND 
  W, 
  H, 
  BARRIS, 
  

  

  ILLUSTEATED 
  

  

  BY 
  JULIUS 
  MAYER 
  & 
  CO., 
  BOSTON, 
  MASS. 
  

  

  PUBLISHED 
  

  

  BY 
  AUTHORITY 
  OF 
  THE 
  LEGISLATURE 
  OP 
  ILLINOIS. 
  

  

  MAY, 
  1883. 
  

  

  