DESCRIPTION OF PLATES 331 



Plate 14 



Cleiothyris royssi (L'Eveille) page 313 



Figures 1-3. Ventral, dorsal, and lateral views of a perfect specimen. 

 Syringothyris sampsoni n. sp page 311 



Figure 4. Posterior view of an imperfect specimen. 

 Athyris lamellosa (L'Eveille) page 312 



Figure 5. Ventral view of a nearly complete specimen. 



Figure 6. Ventral view of a specimen retaining some of the expan- 

 sions of the shell. 

 Dielasma fernglenensis n. sp page 318 



Figure 7. Dorsal view of a distorted specimen. 

 Cleiothyris incrassatus Hall page 313 



Figure 8. Ventral view of a large specimen. 



Figures 9-10. Ventral and dorsal views of an incomplete specimen. 

 Ptychospira sexplicata (W. & W.) page 315 



Figure 11. Ventral view of a perfect specimen (from the Chouteau 

 limestone, Pettis county, Missouri). 

 Cleiothyris prouti (Swallow) page 311 



Figures 12-15. Ventral, dorsal, anterior, and lateral views of a nearly 

 perfect specimen. 



