38 



HUMAN PHYSIOLOGY 



conspicuous features of our age. The importance of 

 thoroughly dividing the food by the teeth has been 

 already insisted upon. Two sets of teeth (Fig. 7) 

 exist in man, and in most of his neighbour animals. 

 The first teeth are known as " milk teeth," and number 

 twenty ; the second set possessing twelve additional 



Fig. 8.- TEETH OF ONE-HALF OF UPPER JAW IN POSITION 

 Seen from above (a), and from the side (fc). 



teeth, and therefore numbering thirty-two. In each 

 jaw the same number and the same arrangement pre- 

 vail (Fig. 8). There are four front teeth or incisors, 

 two canine or eye teeth, four premolars or bicuspids, 

 and finally six molars or back teeth in each jaw. 



