PLATE 19 



Cyrtina missouriensis (Swallow) 

 Page 108. 



Figs. 1-4. Pedicle, brachial, cardinal, and side views of a perfect specimen. (X2). 

 (Callaway limestone of Callaway County.) 



Cyrtina hamiltonensis Hall 

 Page 106. 



Figs. 5-8. Pedicle, brachial, side, and cardinal views of a perfect specimen. (X2). 

 (Mineola limestone of Montgomery County.) 



Cyrtina triquetra Hall 

 Page 108. 



Figs. 9-12. Pedicle, brachial, side, and cardinal views of a perfect specimen. (X2). 

 (Snyder Creek shale of Callaway County.) 



Spirifer annae Swallow 

 Page 99. 



Figs. 13 and 15-17. Pedicle, brachial, cardinal and side views of a perfect specimen. 



(X2). (Snyder Creek shale of Callaway County.) 

 Fig. 14. Surface magnified to show striations. 



Spirifer varicosus Hall 

 Page 102. 



Fig. 18. Brachial valve of a small specimen. (X2). 



(Mineola limestone of Montgomery County.) 



Spirifer asper Hall 

 Page 100. 



Fig. 19. Magnified surface. 



Figs. 20-23. Brachial, pedicle, side, and cardinal views. 

 (Callaway limestone of Callaway County.) 



