136 A MANUAL OF DENTAL ANATOMY. 



The external epithelium of the enamel organ is composed 

 of cells cubical or rounded in form, and is of little interest 

 save in that it is a matter of controversy what becomes of 

 it. Waldeyer holds to his opinion that, after the disap- 

 pearance of the enamel pulp and the stratum intermedium, 

 it becomes applied to the enamel cells, and on the comple- 

 tion of the enamel becomes cornified and converted into 

 Nasmyth's membrane. Kolliker and Legros and Magitot 

 dissent from this opinion, the latter stating that the atrophy 

 of these cells commences early, and that they actually dis- 

 appear prior to the complete atrophy of the organ. For 

 reasons which I have given elsewhere, I do not agree with 

 Waldeyer in this matter, but rather with Magitot. The 

 external epithelium was seen by Nasmyth, Huxley, and 

 Guillot, but it was not very fully described until investigated 

 by Robin and Magitot. 



So simple a matter as the vascularity or non-vascularity 

 of the enamel organ is not yet settled ; Wedl asserts that it 

 contains no vessels, Magitot and Legros sharing this opinion ; 

 Dr. Lionel Beale, on the other hand, stating that a vascular 

 network lies in the stratum intermedium. 



The inner surface of the enamel organ, where it is applied 

 to the dentine bulb, presents a perfectly smooth outline, but 

 its outer surface is indented by numerous papillary projec- 

 tions, into which enter blood vessels of the dental sacculus. 

 These papillae are homologous with, and continuous with 

 those of the gum ; they may sometimes be traced along the 

 neck of the enamel germ, and it is believed that they 

 exercise an important influence on the formation of the 

 enamel, to which I shall again recur. 



The narrow attenuated line of cells by which the enamel 

 organ retains its connection with the stratum Malpighi, 

 whence it was derived, varies much in length and direction 

 in different animals; in man it is short and straight, in 

 the calf it is larger, and undulates in its course. It does 



