PLATE XIII. — {Continued.) 

 Polyp hemopsis Louisville H. & W. 



Page 193. 

 Figs. 16 17. Two views of a specimen enlarged to two diameters. 



GrONIATITES DISCOIDEUS HdU, VWT. OHIOENSES H. & W. 



Page 200. 

 Figs. 18, 19. Lateral and profile views of a specimen. 



Illenus cornigerus H.& W. 



Page 186. 

 Fig. 20. View of the upper side of cephalic shield with the spines partial iy 

 restored. 

 " 21. View of the thoracic portion of the body with the cephalic spines. 





