EXPLANATION OF THE PLATES. 541 



PLATE III. 



Figures of Bacillari/e : Section Echinellea. 



Fig. 1. Synedra , a. fleshy base ; b. fleshy projection 



at the summit, p. 154. 



" 2. Synedra , a. b. different positions, p. 154. 



" 3. Podosphenia? possibly Gomphonema, p. 155. 



" 4. Gomphonema rainutissimum, p. 155. 



" 5. Gomphonema , p. 155. 



" 6. Gomphonema acuminatum ? p. 156. 



" 7. Gomphonema , p. 156. 



" 8. Echinella flabellata, p. 156. 



" 9. Echinella , p. 156. 



" 10. Cocconema , p. 157. 



" 11. Cocconema , 13.157. 



" 12. Achnanthes brevipes, p. 158. 



" 13. Striatella arcuata, p. 158. 



" 14. Naunema , p. 159. 



" 15. Naunema , p. 160. 



" 16. Naunema , p. 160. 



" 17. Naunema , 17. a. single frustule, p. 160. 



" 18. Spicule of Spongilla, p. 161. 



" 19. Probably spiculse of another species of Spongilla. 



" 20. Amphidiscus rotula, p. 162. 



" 21 to 23. Siliceous bodies of organic origin, found with 

 fossil fresh-water Infusoria, p. 162. 



'■' 24. Dictyocha fibula? Ehr. p. 162. 



" 25. Fragment of the preceding, p. 162. 



" 26. Dictyocha speculum, Ehr. p. 163. 



" 27, 28. Siliceous bodies, found with the preceding, p. 163. 



" 29. Binary, triangular, siliceous bodies found with the pre- 

 ceding, p. 163. 



" 30 to 35. Siliceous spiculse, &c. probably derived from ma- 

 rine sponges or Actinia, found with the preceding, p. 163. 



" 36. Scale of -^^p^ milHmetre, magnified equally with the 

 drawings. 



PLATE IV. 



Sections illustrative of Mr. Taylor's Paper, to show the 

 practicability of using minute vertical scales in geolo- 

 GICAL Demonstrations, p. 93. 



PLATE V. 



Fossil Shells from the Southern Atlantic States. 



Fig. 1. Oliva litterata. Lam. p. 108. 



2. Buccinum interruptum, Conr. p. 108. 

 " 3. Conus adversarius, Conr. p. 108. 



