THE DENTAL TISSUES. 



101 



teeth in these classes make me doubt whether the ct priori 

 conclusion of Waldeyer, who believes that the cuticle will 

 be found on all teeth, is not based upon an interpretation of 

 its nature which is incorrect. 



The observation of Professor Huxley, who believed that 

 he found it upon the teeth of the frog, &c., may be suscep- 

 tible of another explanation, to which I shall have to recur, 

 merely premising here that its presence is only certain in 

 Primates, Carnivora, and Insectivora. 



The singular power of resistance to re-agents which 

 characterises it proves nothing more than that it is a tissue, 

 imperfectly calcined, on the border-land of calcification, so 

 to speak, since similarly resistant structures are to be found 

 lining the Haversian canals, the dentiual tubes, the surface 

 of developing enamel, the lacunae, &c. 



In my father's opinion (Dental Surgery, 1859) it is to be 



FIG. 54 ('). 



regarded as a thin covering of cementum, and I have given 

 additional evidence in support of the view in a paper 

 referred to already in the list of works which heads this 

 chapter. 



It now and then happens that the cementum upon a 

 more or less abnormal tooth, instead of ceasing at the neck, 

 (*) Encapsuled lacuna occupying a pit in the enamel. 



