488 



2775. A portion of one of the constituent plates of a molar tooth, from which a 

 transverse slice has been removed and the cut surface polished, showing the 

 central body of dentine, the surrounding layer of enamel, and the thin coat of 

 cement which has begun to be formed upon the enamel. 



Presented by Prof. Owen, F.H.S. 



2776. A tray of separate constituent plates of a molar tooth, in different stages of 

 growth. Presented by Dr. Henderson. 



2777. A tray of separate constituent plates of a molar tooth. 



. Presented by Sir Everard Home, Bart., V.P.R.S. 



2778. A series of ten constituent plates of an upper molar tooth : only the first and 

 second have begun to coalesce at their base. Hunterian. 



2779. The series of plates of the corresponding molar tooth from the opposite side 

 of the upper jaw. Hunterian. 



2780. The second molar tooth, right side, lower jaw, longitudinally and vertically 

 bisected. 



It consists of nine plates, which are all united at their bases by continuity of dentine, and, 

 in the rest of their extent, by the thick covering of cement : the several cavities of the plates 

 communicate with a common pulp-cavity, the walls of which are formed by the bases of two 

 hollow roots. 



Presented by Sir Everard Home, Bart., V.P.R.S. 



2781. The moiety of a vertically bisected upper molar. 



It consists of fourteen plates, of which the bases of the first eight are confluent by continuity 

 of dentine, and the whole are united together by the cement. 



The interblended three substances of which this complex molar consists are well demon- 

 strated in the present section, and the relative density of the enamel, dentine, and cement, 

 is shown by the degree in which they are worn on the surface which has been in use. 



Hunterian. 



2782. The moiety of a vertically bisected upper molar. 



It consists of eleven plates, all of which are confluent at their bases, and all but the last 

 have been in use, the anterior ones being worn down to the common dentinal base. Several 

 roots are developed from this base. 



Presented by Sir Everard Home, Bart., V.P.E.S. 



