﻿PALEONTOLOGY 
  OF 
  ILLINOIS. 
  

  

  SECTION 
  II. 
  

   DESCRIPTION 
  OF 
  FOSSIL 
  INVEETEBKATES. 
  

  

  By 
  A. 
  H. 
  Worthen 
  

  

  and 
  

  

  A. 
  H. 
  Worthen 
  and 
  S. 
  A. 
  Miller. 
  

  

  