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A MANUAL OF DENTAL ANATOMY. 



soon the terminal enlargement, as it grows more deeply 

 into the jaw, alters in form; its base becomes flattened. 



FIG. 64 ( l ). 



1 2 



tr 



and the borders of the base grow down more rapidly than 

 the centre, so that its deepest portion presents a concavity 

 looking downwards ; it might be compared to a bell, sus- 



( l ) Three stages in the development of a mammalian tooth germ (from 

 Frey). a. Oral epithelium heaped up over germ. &. Younger epithelial 

 cells, c. Deep layer of cells, or rete Malpighi. d. Inflection of epithelium 

 for enamel germ. e. Stellate reticulum. /. Dentine germ. g. Inner 

 portion of future tooth sac. h. Outer portion of future tooth sac. 

 i. Vessels cut across, k. Bone of jaw. 



