Development of the Teeth (Figs. 1009 to 1012). In describing the development of the teeth, 

 the mode of formation of the deciduous teeth must first be considered, and then that of the 

 permanent series. 



M.E. 



P.p. 



Fio. 1009. Sagittal section through the first lower deciduous molar of a human embryo 30 mm. long. (Rose.) 

 X 100. L.E.L. Labiodental lamina, here separated from the dental lamina. Z.L. Placed over the shallow dental 

 furrow, points to the dental lamina, which is spread out below to form the enamel germ of the future tooth. P.p. 

 Bicuspioate papilla, capped by the enamel germ. Z.S. Condensed tissue forming dental sac. M.E. Mouth epithelium 



FIG. 



1010. Similar section through the canine tooth of an embryo 40 mm. long, 

 dental furrow. The other lettering as in Fig. 1009. 



Dental furrow 

 Remains of enamel germ 



(Rose.) X 100. L.F. Labio 



Secondary enamel germ 



Meckd's cartilage 



Enamel organ 

 Dental papilla 



Mandible 



Fio. 1011. Vertical section of the mandible of an early human fetus. X 25. 



