PLATE LXV 



PAGE 



Fig. 1. LYRIOPECTEN TRICOSTATUS (Vanuxem) 649 



Left valve with characteristic surface markings. Jennings formation, 

 Chemung member, Allegany County, near West Virginia line. 



Pig. 2. MODIOMORPHA SUBANGULATA Hall var 650 



Right valve. Jennings formation, Chemung member, Williams Road, 

 Polish Mountain, 2382. 



Fig. 3. GONIOPHORA HAMILTONENSIS Hall 651 



Left valve. Jennings formation, Parkhead member, Western Mary- 

 land Railroad, 2 miles west of Pawpaw, 1485. 



Figs. 4-6. GONIOPHORA TRUNCATA Hall 651 



4. Cast of interior of left valve. 



5. Cast of interior of right valve. 



6. Left valve. 



Jennings formation, Parkhead member, Williams Road, Polish 

 Mountain, 1660. 



Fig. 7. GONIOPHORA GLAUCA Hall 652 



Right valve. Jennings formation, base of Parkhead member, White 

 Sulphur Branch, 4 miles southeast of Pratt. 



Figs. 8-10. CYPRICARDELLA BELLISTRIATA (Conrad) 653 



8. Left valve. 



9. Right valve. 

 10. Left valve. 



Hamilton formation, New York. 



Figs. 11-15. CYPRICARDELLA MARYLANDICA n. sp 654 



11. Right valve. 



12. Right valve somewhat distorted. 



13. Internal cast of right valve. 



14. Left valve of normal outline. 



15. Right valve expressing the correct characters of the exterior. X 2. 



Jennings formation, Chemung member, Deer Park. 



Figs. 16-18. CYPRICARDELLA GREGARIA (Hall) 654 



Internal casts of left valves. Jennings formation, Parkhead (?) mem- 

 ber, National Road, west of Green Ridge. 



148 



