PLATE XXXVIIa. 



PAGE 



Fig. 1. Raphistoma affine, Foerste 550 



1. u, 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. Beixerophon (Bucania) exiguds, Foerste 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 strise of growth. T. F. Q. Cabinet of Dr. 

 Chas. Welch. 



BeUvEROphon (Bucania) opertus, Foerste 548 



, 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. 



Subdutes (Polyphemopsis) planilateralis, Foerste 555 



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

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



Subuwtes directds, Foerste 554 



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

 near base of Clinton at Huffman's quarry. 



Pleurotomaria filitexta, Foerste 550 



, lateral view ; b, apical view. "Orthoceras block," Huffman's quarry. O. 



Straparolltjs (of. Oriostoma) incarinatum, Foerste 552 



, lateral view ; b, apical view. "Orthoceras block," H. O. 

 Fig. 8. PI.ATYCERAS ( Pl^ATYSTOMA ) NlAGARENSE, Hall, var. CUNTONEN- 



se, Foerste 552 



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



. Cyclonema bilix, var. varicosum 550 



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

 fragments in the writer's collection. 



Orthoceras inceptum, var. acceleratum, Foerste 545 



SH. O. Collection of Geo. Caswell. 



Co^eolus Cijntonensis, Foerste 547 



SH. O. 



Conularia biuneata, Foerste 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, Foerste 522 



Huffman's quarry, Ohio. 



Sphaerexochus pisum, Foerste 528 



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

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



Lichas phi/yctainoides ? Green 529 



A glabella, SH. O. 



Atrypa i<aTi-corrugata, Foerste , 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. 



