TEETH OF PHYSETER / 



ing the inandibultir teeth the defective condition hero referred 

 to must be borne in mind. I shall have, for example, to indicate 

 actual structural differences between the teeth of the mandibles 

 and those of the maxillae and premaxillae. 



These teeth are readily comparable at first sight with the 



Text-fig. 3. 



«• 



As Text-tig. 2, but the rudiment of permanent tooth is larger. 



teeth of other mammals in a corresponding stage of develop- 

 ment. The tooth rudiment shown (Text-fig. 4) as a bell- 

 shaped swelling seems to be clear ; and beyond this, i.e. distally 

 from the place of origin of the dental lamina, is a prolongation 

 which would seem to correspond to the residual lamina of 

 other teeth. They all presented more or less the appearance 

 shown in Text-figs. 2, 3, 4. The entire organ developed from 

 the enamel germ often lay closely adpressed to one side of the 



