EXPLANATION OF PLATES. 



PLATE. 23.— Continued PAGE 



BLOTHROPHYLLUM GREENEI, N. Sp. (RoTvIey.) 68 



FIGS. 16—17. — Side and calix views of a large specinun. 

 FIG. 18. — Side view of another large irregular shaped 



individual. 

 FIGS. 19-20 — Side views of 'two smaller specimens. 



SPIRIFER LATERALIS, Var. DELICATUS, N Var. (Rowley.) 68 



FIG . 21. — Cardinal view of a specimen. 



FIGS. 22-23. — Front and brachial views of another specimen. 



ORBICULOIDEA PARVA, N. Sp. (Rowley.) m 



FIGS. 24-25. — Two views of the type specimen. 



CRANIA ROBUST A, N. Sp (Rowley.) 6i» 



FIGS. 26-27. — Two views of the type specimen. 



CRANIA DEPRESSA, N. Sp. (Rowley.) 6i) 



FIGS. 28-29. — External and internal views of a de- 

 tached upper valve. 



PRODUCTUS PARVICOSTATUS, N. Sp. Rowley. 70 



FIGS. 30-31. — Side and ventral view of the type. 



PLATYCERAS CIRCULARIS, N. Sp. (Rowley.) 70 



FIGS. 32-33. — Side view and view of the aperture. 



LEPETOPSIS LEVETTEI, White. Rowley. 



FIGS. 34-35. — Two views of a specimen from the Keokuk 

 Limestone. 



