292 



PLATE XIV 



Page 



Figs. 1 to 4. Astartella varica McChesney 243 



Upper Pottsville (McArthur)?: Hocking County, Carbon 

 Hill. 



Fig. 1. Left valve. 



Fig. 2. Right valve of another specimen. 



McArthur limestone: Vinton County, Elk Township, 

 Moore mine, Locality 84. 



Fig. 3. "Squeeze" of right valve showing the radiating 

 lines which characterize the middle layer of shell sub- 

 stance. 



Fig. 4. Dorsal view of a complete specimen. 

 Figs. 5 to 8. Pleurophorus immaturus Herrick 236 



Fig. 5. Left valve of young specimen corresponding to 

 typical P. immaturus of Herrick. x2 Lower Mercer 

 limestone: Licking County, Flint Ridge, Locality 47. 



Fig. 6. "Squeeze" of external mold of right valve of a 

 mature specimen corresponding to .P. subcostatus of 

 Herrick. McArthur member: Vinton County, Elk 

 Township, Moore mine, Locality 84. 



Fig. 7. Right valve of a specimen with the radiating mark- 

 ings evanescent. Lower Mercer limestone: Licking 

 County, Flint Ridge, Locality 47. 



Fig. 8. Enlargement of the surface of the external- mold 

 illustrated in Fig. 6, showing the spinulose surface 

 structure. x24 

 Figs. 9 to 11 . Pleurophorus spinulosa n . sp : 239 



Lower Mercer limestone: Licking County, Bald Knob, 

 Locality 46. 



Fig. 9. "Squeeze" of external mold of left valve of one 

 of the two cotypes. 



Fig. 10. "Squeeze" of external mold of right valve of the 

 other cotype. 



Fig. 11. Enlargement of the surface of the external mold 

 illustrated in Fig. 9, showing the spinulose surface struc- 

 ture. x24 

 Fig. 12. Prothyris elegans Meek 195 



Left valve of internal cast. Lower Mercer limestone: 



Licking County, Flint Ridge, Locality 47. 

 Figs. 13, 14. Patellostium montfortianum (Norwood and Pratten) 251 



Fig. 13. Small specimen with outer lip missing. Lower 

 Mercer limestone: Perry County, Somerset, Locality 

 35. x2 Hyde collection 823. 



Fig. 14. Larger specimen with outer lip partly preserved. 

 McArthur member: Vinton County, Elk Township, 

 Moore mine, Locality 84. 



