PLATE 33. 
Spirifera eimbriata .. 
Page 
214 
Figs. 1 - 21. 
1. An imperfect dorsal valve of this species, from the Orisltany sandstone. 
2. A view of an imperfect ventral valve of this species. 
3. The cast of a ventral valve, showing the muscular impression. 
4. A view of a cast of a dorsal valve. This, and the two preceding figures, are from speci¬ 
mens found in the Schoharie grit. 
5. 6. Dorsal and ventral views of a small individual, from the Corniferous limestone. 
7. A dorsal view of an individual of medium size, from the Corniferous limestone. 
8-11. Profile, dorsal, ventral and front views of a full grown individual, from the Corniferous 
limestone. 
12, 13. Dorsal and ventral views of a small individual. 
14. Cardinal view of a short individual of this species. 
15. A ventral view of another specimen which preserves the fine setiform spires of the surface. 
16 - 19. Profile, front, dorsal and ventral views of a large sized specimen. Figures 12 - 19 
are from specimens from the soft shales of the Hamilton group. 
20. A cardinal view of a cast of this species, from the Hamilton group, Hardy county, Ya. 
21. Enlargement of the surface of specimen fig. 18, showing the pustulose markings. 
Figs. 22 - 30. Spirifera sttbumbona. 234 
22. 23. Dorsal and profile views of a specimen of this species. 
24. Dorsal view of another individual. 
25-29. Dorsal, ventral, profile, cardinal and front views of a large and rather gibbous specimen. 
30. Enlargement of the surface, showing the small pits that result from a partial exfoliation of 
the shell. These figures are from specimens occurring in the limestones of the Marcellus 
shales. 
Figs. 31-35. Spirifera prematura. 250 
31. A ventral valve of a small individual. 
32. A larger dorsal valve, showing the pustules of the surface. This, and the preceding figure 
are from New York specimens. 
33. Cast of another dorsal valve, showing the impression of the median septum. 
34. Yiew of the cast of a ventral valve. 
35. Cast of ventral valve of another individual, having a much larger rostral cavity. This, and 
the two preceding figures, are from specimens occurring near Meadville, Pa. 
