I'LATlJ XXVI. 



I'AUE. 



ORTHOCERAS ILLIXOIEJJSE Worthen , (S 



Fig. 1. Viuw of outer eliamber with septa attached. 



Fig. : n. View septate portion, 



Fitt 1 '(. Transverse section showing position of siphunele. 



XAUTILUS MONTGOMERYENSIS Worthen , , h 



Fig. 2. Lateral view; natural size. 



OKTHOCEKAS OKAVENSE Worthen IKI 



Fig. . View of a nearly perfect specimen; natural siz. 



OETHOUEBAS LASALLENSE Worthen ,4,, 



Fig. 4. View of a specimen natural size. 

 Fig. 4,,. Fragment of tho test enlarged 2X. 



GONIATITES MONROENSIS Worthen 150 



Fig. 5. Lateral view showing form of the septa>. 



