10 



ILLUSTRATIONS. 



Plate xlviii. Gasteropods . 



xlix. Gasteropjds. 



1. Gasteropods. 



li. Gasteropods. 



lil . Gasteropods . 



liii . Ceph alopods . 



liv. Cephalopoda. 



FlGUiUC 1. 



2. 

 3. 



4. 

 5. 

 6. 



10. 

 11. 



Section at Railroad Bridge nortli of Fredericktown, Madison county, show- 

 ing contact of Cambrian and porphyry. 



Ideal section of the Deposition of the Ozark Rocks. 



Relation of Saint Louis and " Warsaw " beds at Keokuk, Iowa. 



False Bedding of Oolite at Ste. Genevieve. 



Relations of the Aux Vases Sandstone. 



Rocks at Chester (Illinois) showing Coal Measure sandstone resting on Kas- 

 kaskia limestones and shales. 



Line of Juncture of figure 6. 



Lower Coal Measures resting on Brecciated Saint Louis limestone at 

 Keokuk, Iowa. 



Plan of Actinocrirus. 



Variation of Capulus equilateralis (from above) . 



Variation of Capulus equilateralis (from side) . 



