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 



awa}^. 



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 Mosasaurus Hoffmanni. 



8. Outline of the transverse section of the tooth of Mosa&awrm Maximiliani. 



9. Outline of the transverse section of the tooth of Mosa-sanrus gracilis. 



