platp: III. 



Paga 



Figs. 1 and 2. Schistoceras hildkethi Morton 107 



Upper Coal Measures, Cambridge, Ohio. 

 Figs. 3-13. Shumardites simoxbsi Smith, gen. et sp. nov 135 



Upper Coal Measure.s, Cisco formation, Graham, Tex. 



Figs. 3 and 4. Views of young shell, at diameter of 22 mm., showing gastrioceran shape of 



whorl. 

 Figs. 5 and Ij. Partial restoration of the above specimen. 

 Fig, 7. Septa showing gastrioceran character and beginning of division of lateral lobe, at 



diameter of 7 mm., 10 times enlarged. 

 Fig. 8. Septa at diameter of 12 mm., transitional from Parakgoceras to Schistoceras: 3.6 



times enlarged. 

 Fig. 9. Septa at diameter of IH uuu. (one-half reVdUition more than tig. 8), 3.6 times 



enlarged. (Septa inverted. ) 

 Fig. 10. Septa at diameter of 22 mm. (one-half revolution more than fig. 9), 4 times 



enlarged. 

 Fig. 11. Septa at 38 mm. (one-half revolution more than fig. 10), showing mature 



characters; drawn from specimen shown in figs. 12 and 13, l.ti times enlarged. 

 Figs. 12 and 13. Type specimen, natural size. 



Note. — Figs. 1 and 2 are figs. 40a and 406 of PI. 1 of Etude sur les Goniatites. 



154 



