ON CESATODUS FOSSTEEI. 149 



EXPLANATION OF THE PLATES. 



PI. 4, fig. 1. Ceratodus Forsteri (Kreft) from a stuffed specimen in the 

 Bristol Museum, presented by the author, J nat. size. 



fig. 2. Scale of the same, the dark part is the portion not overlapped 



by adjoining scales, nat. size. 



fig. 3. Eight tooth of upper jaw of the same, nat. size. 



PL 0, fig. 1 . Interior view of upper jaw, showing the apertures of the 

 nostrils surrounded by the soft parts ; the vomerine teeth 

 in front, and the pair of grinding teeth behind ; the 

 pterygo- palatine and basal ossifications are seen ; the dark 

 portion behind represents the cartilaginous roof of gill 

 cavity (after Dr. Guenther) | nat, size. 



fig. 2. A fossil tooth from Aust Cliff (from the Higgins collection) 



nat. size. 



