PLATE LXX 



PAGE 



Figs. 1-5. SPIRIFER MURCHISONI Castelnau 411 



1. Dorsal view of an average specimen. Cumberland. 



2. Internal cast of ventral valve retaining portion of shell, same 



locality. 



3-5. Dorsal, ventral, and side views of the form with angular plica- 

 tions. Warren Point, Penna. 

 Oriskany formation, Ridgely member. 



Figs. 6, 7. SPIRIFKR MURCHISONI YAR. MARYLANDICUS Schuchert n. var. . . . 413 

 Dorsal and side views. Oriskany formation, Ridgely member, Cum- 

 berland. 



Figs. 8-10. SPIRIFER HARTLEYI Schuchert n. sp . . . ; 413 



Dorsal, ventral, and side views of the type. Oriskany formation, 

 Ridgely member, Cumberland. 



Figs. 11-13. SPIRIFER PERDEWI Schuchert 414 



11, 12. Dorsal and ventral views of a small specimen. 



13. Dorsal view of a large specimen. 



Oriskany formation, Ridgely member, Cumberland. 



Figs. 14-16. SPIRIFER TRIBUARIUS Schuchert n. sp 414 



14. Dorsal view. 



15, 16. Dorsal and ventral views of another individual. 



Oriskany formation. Shriver member, Cumberland. 



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