SI 4 EXPLANATION OF THE PLATES. 



Figs. 7, 8. Casts of unknown bivalves, p. 96. 



Figs. 10, 11, 12, 14. Various specimens of Rostellaria carinata, p. 86. 



Fig. 13. Ampullaria canaliculata, p. 87. 



Fio-. 15. The Leaked part of the lower valve of Inoceramus concentric us, p. 95. 



Fig. 16. Inoceramus sulcatus, p. 95. 



Fio-s. 17, 18. Belemnites Listeri, p. 88. 



Fig. 19. Inoceramus concentricus, p. 95. 



Fig. 20. A specimen of Inoceramus, shewing the crenulated hinge, p. 96. 



Fig. 21. DentaUum ellipticum, p. 87. 



Fio-. 22. The upper surface of Turbinolia Konigii, p. 85. 



Fi<^. 2S. Variety of Belemnites Listeri, p. 88. 



Fio-. 24. View of the base of Turbinoha Konigii, p. 85. 



Fio-. 25, Cast of the interior of Dentahum ellipticum, p. 87. 



Figs. 26, 27. Nucula ovata, p. 94. 



Fio-. 28. An unknown species of Dentalium, p. 87. 



Figs. 29, 30. Hamites attenuatus, p. 93. 



Figs. 31, 32. Probably a species of Natica, p. 87. 



Fig. 33. Cast of a species of Area ? or Nucula ? 



Fig. 34. Auricula incrassata, p. 110. 



TABLET XX. 



Fig. 1. Nautilus elegans, from the Grey chalk marl at Middleham, p. 112. 

 Fio-. 2. Ammonites Sussexiensis, from Hamsey, p. 114. 



TABLET XXI. 



Nautili, and Ammonites, from the chalk, and chalk marl, near Lewes. 

 Figs. 1, 4, 8. Casts of Nautilus elegans, in a young state, p. 113. 

 Figs. 2, 5, 7. Varieties of Ammonites wrzaMS, p. 115. 

 Fig. 3. Ammonites planus, from the Blue marl, p. 90. 

 Fig. 6. Kmmomies falcatus, p. 117. 

 Fio-. 9. Costated variety of Ammonites Mantelli, p. 113. 

 Fig. 10. Ammonites Sussexiensis, p. 114. 



Fjo-. 11. lautus, from the Blue marl, p. 91. 



Fio. 12. A portion oi Ammomtesfalcatus, shewing the ambit, p. 118. 



Fig. 13. Fragment of Ammonites splendens, p. 89. 



Figs. 14, 15. Nautilus inequalis, p. 88. 



Fig. 16. Ammonites Woollgari, p. 197. 



Fig. 17. A cast of A. splendens, p. 89. 



Fig. 18. Ammonites curvatus, p. 118. 



