TAB. IX A. 

 Leiodon anceps, nat. size. 



Fig. 



1. Part of the lower jaw with teeth. 



2. Diagrammatic section of a tooth, showing the pulp-cavity, which contained a 



siliceous mass, fig. 2'. 

 (Copied from the figures in the ' London Geological Journal,' 1 846, Pis. iv and vi.) 



3. A portion of the same or a similar jaw, with the crowns of the teeth broken 



away. 



4. Upper or alveolar surface of the same portion of jaw. 



5. The crown of one of the teeth from the same portion of jaw. 



5*. The base of the same tooth. 



5**. Outline of the transverse section near the base of the same tooth. 



The above specimens are from the Chalk of Norfolk, or to the North of the 

 Thames ; and are in the Collection of Edward Charlesworth, Esq., of York. 



6. The crown of a tooth of Leiodon anceps. 



From the Chalk of Sussex. In the Collection of Henry Catt, Esq., of Brighton. 



7. Outline of the transverse section of a tooth of Mosasaurws Hoffmanni. 



8. Outline of the transverse section of the tooth of Mosasaurus Mawimiliani. 



9. Outline of the transverse section of the tooth of Mosasaurus gracilis. 



