Pig. 





i . Ustheria minuta. 



2. 









3. 





4. 





5- 





6. 





7. 



, 



8- 



>7 



PLATE n. 



-Left valve, well-preserved ; Pen dock, Worcestershire : X 6 diam. 

 Dorsal profile of the same : X 6 diam. 

 Portion of the surface of the same : X 50 diam. 

 Right valve ; Somerton, Somersetshire : X 6 diam. 

 Left valve ; Shrewley, Warwickshire : X 6 diam. 

 Dorsal profile of the same : X 6 diam. 

 Portion of the surface of the same : X 50 diam. 

 Portion of the surface of a specimen from Prome, Somersetshire, 

 showing a smaller reticulation : X 50 diam. 

 9. Estheria minuta, yw:.Brodieana{^. 66) — Right valve; Linksfield, Elgin: X 6 diam. 



10. „ „ „ Portion of the surface of the same : 



X 50 diam. 



11. • „ „ „ Portion of the surface of another specimen, 



from the same place, showing a more 

 linear reticulation : X 50 diam, 



12. ,, • „ „ Right valve; Wainlode, Gloucestershire: 



X 6 diam. 



13. „ „ „ Dorsal profile of the same : X 6 diam. 



14. „ „ „ Left valve, from the same place : X 6 diam. 



15. „ „ „ Portion of the surface of another speci- 



men, from the same place : X 50 diam. 



16. Estlieria Mangaliensis (p. 78). — Left valve; Mangali, Centrallndia: X 6 diam. 



17. „ „ Portion of the surface : X 25 diam. 



18. „ ,, Portion of an interspace : X 100 diam. 



19. „ ,, Portion of the surface where the ridges are lost 



in overlapping laminae : 100 diam. 



20. „ ,, Right valve of a subquadrate individual : X 6 diam, 



21. „ „ Left valve of a young individual, ovate-oblong : 



X 6 diam. 



22. „ „ Right valve of a young individual, subovate : X 6 



diam. 



23. ,, „ Right valve of a young individual, subquadrate 



or suborbicular : X 6 diam. 



24. Estlieria Kotahenm (p. 81). — Left valve; Kotah, on the Pranhita, Central India: 



X 6 diam. 



25. „ „ Portion of surface : 100 diam. 



26. Estheria ovata {^. 84). — Right valve of a youngish individual; Prince Edward, 



near Richmond, Virginia : X 6 diam. 



27. „ „ A pair of valves (somewhat restored) ; Prince Edward, 



Richmond : X 6 diam. 



28. „ „ Right valve ; Harding's pit, near Richmond, Virginia : 



X 6 diam. 



29. „ „ Portion of the surface of the same : X 50 diam. 



30. „ „ Portion of the surface of the same : X 100 diam. 

 31—38. „ Portions of the surface : X 50 diam. Figs. 31, 32, 33, 



36, and 38, are from Richmond ; figs. 34, 35, and 

 37 are from Dan River. 

 39. Estheria tenella i^. 31). — Right valve; Lanarkshire: X 6 diam. (Por its orna- 

 ment, see PL V, fig. 7.) 



