PLATE IV. 



Ceratodus polymorphous — Palatal Teeth. 



Figs. 

 1 — 11. Specimens from Aust Cliff (Bristol Museum). 



Figs. 1, 2, 6, and 11, have the first denticle broken to such an extent as to 

 alter the outline of the tooth. Fig. 2 is broken from x to x.' Fig. 11 is 

 probably a palatal tooth with no distinct fourth denticle. Fig. 10 should 

 also be compared with PI. V, figs. 5 and 9. 



The following series may be noted : 

 (1.) 1,3,8,9,11. ' 

 (2.) 1, 5, 4. 

 (3.) 1, 5, 10. 

 (4.) 1, 2, 3, 8, 7, 11. 







