'PLATE XXXVIItf. 



PAGE 



Fig. 1. Raphistoma affine, FcErste 550 



1. a, Apical view, magnified two diameters ; b, apertural view ; c, umbilical view. In 

 all three figures the details of the aperture are restored from fragments and by 

 tracing out the outline in accordance with the striae of growth. T. F. O. Cabi- 

 net of Dr. Chas. Welch. 



Fig. 2. Beeeerophon (Bucania) exiguus, Fcerste 548 



2. a, Posterior view ; b, apertural view ; c, umbilical view, the rapid expansion of the 

 outer lip not well shown. In all three figures the outline of the outer lip has 

 been restored from the course of the striae of growth. T. F. Q. Cabinet of Dr. 

 Chas. Welch. 



Fig. 3. Beeeerophon (Bucania) opertus, Fcerste 548 



3. «, Posterior view ; b, umbilical view. In both figures the outlines of the aperture 



are restored from the course of the striae of growth. H. I. 



Fig. 4. Subueites (Poeyphemopsis) peanieaTERAEIS, Fcerste ; 555 



4. a, Natural size ; b, the same magnified three diameters, apertural view ; c, posterior 



view. S. H. O. Collection of Geo. Caswell. 



Fig. 5. Subueites directus, Fcerste 554 



5. a, Apertural view; b, apical posterior of another specimen.. "Orthoceras block " 



near base of Clinton at Huffman's quarry. 



Fig. 6. PlEurotomaria fieitexta, Fcerste 550 



<i. a, Lateral view; b, apical view. "Orthoceras block," Huffman's quarry. O. 



Fig. 7. Straparoleus (of. Oriostoma) incarinatum, Fcerste 552 



7. a, Lateral view ; b, apical view. "Orthoceras block," H. O. 



Fig. 8. PeaTyceras ( PeaTystoma ) Niagarense, Hall, var. Ceintonen- 



SE, Fcerste 552 



8. Showing the loosening coil. Pennsylvania collection of Prof. E. W. Claypole. 



Fig. 9. Cyceonema biljx, var. VARICOSUM..: 550 



9. Apertural view. TF. O. Collection of Dr. Chas. Welch; the aperture restored from 



fragments in the writer's collection. 



Orthoceras inceptum, var. acceeeratum, Fcerste 545 



SH.O. Collection of Geo. Caswell. 



Coleoeus Ceintonensis, Fcerste 547 



SH. O. 



Conuearia bieineata, Fcerste 547 



View of a portion of the small fragment, showing the bilineate character of trans- 

 verse striae, magnified about fifteen diameters. SH. O. 



Acidaspis brevispinosa, Fcerste 522 



Huffman's quarry, Ohio. 



Sphaerexochus pisum, Fcerste 528 



a. View of glabella from above ; b, lateral view. Niagara shales at Eockport, N. Y. 

 Secured from Dr. E. N. S. Ringueberg. 



Ltchas phlvctainoides? Green 529 



A glabella, SH. O. 



Atrypa eati-corrugaTa, Fcerste 591 



a, b, c. Three lateral views to show the varying convexity of the shell, and the 

 strength of the corrugations; d, view of the brachial valve. "Orthoceras block," 

 Huffman's quarry. 



Fig. 



10. 

 10. 



Fig. 



11. 



11. 



Fig. 



12. 



12. 



Fig. 



13 





13. 



Fig. 



14. 

 14. 



Fig. 



15. 

 15. 



Fig. 



16. 



hi. 



