8o 



THE CONNECTIVE TISSUES. 



[CH. V. 



A layer of columnar epithelium cells in contact with the 

 dentine. These are called the enamel cells, or adamanto- 

 blasts. 



Two or three layers of smaller polyhedral nucleated cells 

 the stratum intermedium of Hannover. 



d. 



Fig. 101. Highly magnified view of a piece of the enamel organ in a kitten's canine. 

 d, superficial layer of dentine, e, newly formed enamel stained hlack by osmic acid. 

 T, Tomes' processes from the adamantoblasts, ad. ; ttr. int., stratum intermedium of 

 the enamel organ, p, branched cells of the enamel pulp. (After Rose., 



3. A matrix of non-vascular jelly-like tissue containing stellate 

 cells. 



4. An outer membrane of several layers of flattened epithelium 

 cells. 



The first three layers on an enlarged scale are seen in fig. 

 101. 



The enamel prisms are formed by the agency of the ends of 

 the adamantoblasts which abut on the dental papilla. Each 

 forms a fine deposit of globules staining with osmic acid and 

 resembling keratin in its resistance to mineral acid. At one 

 time it was believed that each adamantoblast was itself calcified 

 and converted into an enamel prism, but this view has been 

 disproved by recent research. The layer of keratin-like material 

 is outside the bodies of the cells, although a process of each 

 adamantoblast extends into it as a tapering fibre (process of 

 Tomes), and it is usually produced simultaneously with the first 

 layer of uncalcified dentine ; when it undergoes calcification, the 

 first layer of enamel is complete. The adamantoblasts then 



