﻿GEOL. 
  SOC. 
  AM., 
  MEMOIR 
  76 
  

  

  PALMER, 
  PL. 
  19 
  

  

  TEGULA, 
  CYTHNIA, 
  HALISTYLUS, 
  TEINOSTOMA, 
  LIOTIA, 
  ARENE, 
  HOMALOPOMA. 
  

   ASTRAEA, 
  LACUNA, 
  AND 
  PHASIANELLA 
  

  

  