MANUAL OF DENTAL ANATOMY 



HUMAN AND COMPAKATIVE. 



CHAPTER I. 



THE TEETH OF MAN. 



THE range of the subject of Dental Anatomy turns upon 

 the meaning which is attached to the word " Tooth ;" but, 

 although this chapter might most appropriately open with 

 a definition of this word, it is very much easier to explain 

 what is ordinarily understood by it, than to frame any 

 single sentence which shall fulfil the requirements of logical 

 definition.X Most vertebrate and a great many invertebrate 

 animals have certain hard masses in or near to the orifice 

 of the alimentary canal, i.e. y the mouth ; by these hard 

 masses, sometimes of bony and sometimes of horny nature, 

 various offices in connection with the prehension or com- 

 minution of food are performed, and to them the term 

 " teeth " is applied. In many animals teeth have come to 

 be used for other purposes, such as for sexual warfare j but 

 it can hardly be doubted that teeth have primarily to do 

 with the nourishment of their possessor/^ 



The subject of the homologies of the teeth cannot be fully 

 entered upon until the details of their development have 



