ORGANS AND PROCESSES OF DIGESTION 55 



XXXIV. THE TEETH. 



Apparatus. A hand mirror, a molar tooth sawed in vertical sec- 

 tions, an apple. 



Directions. A. Kinds of Teeth. With the aid of the 



mirror and the finger count the number of teeth on each jaw. 

 Is the number the same? Note that they may be divided 

 into four classes according to shape. How many broad 



a 



d 



FIG. 28. a, incisors; 6, canines; c, premolars; d, molars. 



teeth (incisors) have you in the front of each jaw? How 

 many with one point on the surface (canines)! How many 

 with two surface points (bicuspids or premolars)? With 

 more than two surface points (molars)? Tabulate these 

 numbers as follows: 



Grand Total 



