NASMYTH'S MEMBRANE 



343 



This detachment of other cells than those constituting 

 the enamel organ will account for the presence, in the floated 

 preparations of the membrane, of the rounded cell masses 

 and the cell nests above described, and we must consider 

 that Nasmyth's membrane consists not only of the external 

 epithelium, but also, and more evidently, of the two inner- 

 most layers of the enamel organ, which have not disappeared 

 on the eruption of the tooth but remain attached to the 

 enamel. 



FIG. 232. Partial detachment of Nasmyth's membrane from 

 follicle. Columnar cells, many vacuolated. ( x 250.) 



Summary 



In preparations of Nasmyth's membrane by separation 

 from the surface of the enamel by acids, cells are seen which 

 do not appear to have any connexion with the enamel organ, 

 such as the rounded bodies and the cell nests. 



These preparations would appear to be explained by the 

 longitudinal sections of the tooth in the follicle. It is seen 

 that the attachment of the enamel organ with other altered 

 and degenerated cells in contact with it is very slight, and 

 these latter cells show a tendency to separate from the 

 follicle with those of the enamel organ. It is evident that 



