MASTICATION. 



Ill 



teeth is thirty- two, the shapes and names of which it is 

 proper here to present the student. 



Fig. 75. 

 a a b c c d d d 



The upper row, Fig. 75, represents the upper teeth on 

 the left side ; the lower one, the under teeth on the same 

 side. Those situated in front of the jaw, the bodies of 

 which are wedge shaped, are called the incisores, or cut- 

 ting teeth, a a. At the sides of the cutting teeth, and 

 posterior to them, stand the cuspidati, or canine teeth, b. 

 The bodies of these are also somewhat w r edge-shaped, 

 and are usually called the eye teeth. Next behind the 

 canine, come the bicuspidati, or the two first grinders, 

 c c. The bodies of these are oval, with the surfaces of- 

 ten slightly indented. Behind these stand the molares, 

 d d d, forming the third, fourth, and fifth grinders. In 

 the upper jaw, the three last grinders generally have 

 each three fangs, while the corresponding ones of the 

 under jaw have only two. 



The use of the incisors is for cutting and dividing the 



What number of teeth has the human species ? What are their 

 names, and how are they situated with respect to each other 1 



