PLATE XXXI. 



Rhynchonella louisvillensis. 

 Fig. 1-4. Dorsal, ventral, front and profile view of a specimen. Page 77 



Murchisonia petilla. 



Fig. 5. View of an internal cast. Page 170 



Rhynchonella gainesi. 



Fig. 6, 7. Dorsal view of two specimens. Page 76 



Fig. 8, 9. Front and ventral view of a specimen. 



Spirifera mucronata. 



Fig. 10, 11. Ventral and dorsal view of a specimen. Page 126 



Tentaculites scalariformis. 

 Fig. 12. View of a specimen, enlarged xi. Page 156 



Spirifera sculptilis. 



Fig. 13. Ventral view of a valve. Page 132 



Centronella glans-fagea. 

 Fig. 14-17. Front, pronie s dorsal and ventral view of a specimen. 153 



