PLATE VIII 



PAGE 

 FigS. 1-4. LlNGULELLA (?) PALIFORMIS Hall 124 



1. Interior of dorsal valve (?). Evitts Creek. 



2. Ventral valve, showing faintly the pedicle-groove. Evitts Creek. 



x iy 2 . 



3. A partly exfoliated valve. Evitts Creek. X 1%. 



4. Ventral valve, the specimen showing the pedicle-groove. Williams 



Road, 3% miles southeast of Cumberland. X 2. 

 Romney formation, Hamilton member. 



Pig. 5. LINGULA DELIA Hall (?) 125 



Ventral valve (?) showing strong median septum. X 1%. Romney 

 formation, Hamilton member, Evitts Creek. 



Fig. 6. LINGULA LIGEA Hall (?) 126 



Interior of partly exfoliated valve. X 2y 2 . Romney formation, 

 Hamilton member, 21st Bridge. 



Figs. 7, 8. LINGULA CF. NUDA Hall 127 



7. Partly exfoliated distorted valve. X 2y 2 . Romney formation, Onon- 



daga member, Williams Road, 3% miles southeast of Cumber- 

 land. 



8. Partly exfoliated ventral valve (?). X 1%. Romney formation, 



Hamilton member, Oldtown Road, east of Cumberland. 



Figs. 9, 10. LINGULA NUDA Hall 127 



Separate valves showing the usual variety of form in this species. 

 Hamilton formation, New York. 



Fig. 11. LINGULA CF. COMPTA Hall and Clarke 128 



View of crushed and broken specimen. X 1*4. Romney formation, 

 Hamilton member, Evitts Creek. 



Figs. 12, 13. LINGULA CLARKI n. sp 128 



Partly exfoliated valves showing strong median convexity. X 3. Rom- 

 ney formation, Hamilton member, 21st Bridge. 



Figs. 14-17. ORBICULOIDEA LODIENSIS VAR. MEDIA (Hall) 129 



14. Interior of dorsal valve. X 2. 



15. Exterior ventral valve showing the pedicle-groove. X 2. 



Romney formation, Hamilton member, Evitts Creek. 



16. Interior of a partly exfoliated ventral valve. The more exfoliated 



portions are smooth, not striated, as indicated by figure. Bells 

 Gap, Va. 



17. Natural cast of the exterior of ventral valve, showing concentric 



striae. East of Cumberland. 

 Romney formation, Onondaga member. (After Kindle.) 



