PLATE 2 



EXPLANATION OF FIGURES 



7 Section through a back tooth at birth showing relative thickness of enamel 

 the deposition of which has been completed at this stage. The germ of the per- 

 manent tooth appears as a narrow cord of cells at the lingual side of its milk 

 predecessor. X 70. 



8 Section through germ of the eighth back tooth at birth (108 mm.). X 380. 



9 Section at birth through the cord of cells which represents the germ of the 

 permanent tooth. X 1800. 



10 Section through enamel and enamel organ of permanent tooth a few 

 months after birth. X 560. 



686 



