TOOTH DEVELOPMENT DASYPUS NOVEMCINCTUS 



6G9 



in 71, 73, and 78 nnii. embryos, there are present collections of 

 epithelial cells, which from their shape, might be interpreted as 

 degenerating enamel organs. In the 82 mm. embryo, the first 

 tooth is absent in two cases, but in the third, I found it repre- 



/ a 



Fig. 10 Diagrammatic section through the six front teeth of a full term fetus. 

 The stippled portion represents dentine, a-/, teeth 6-1 respectively. 88. 



sented by a small dental papilla capped with dentine. In the 

 108 mm. embryo, this tooth again appears — but in one-half of 

 the jaw only; at this stage, it is an almost solid mass of dentine. 

 An exceedingly thin layer of enamel is present and a mass of epi- 

 thehal cells occurs over the part of the tooth representing the 



JOURNAL OF MORPHOLOGY, VOL. 27, NO. 3 



