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A MANUAL OF DENTAL ANATOMY. 



As the teeth during their development are thus lying down 

 parallel with the length of the jaw-bone, when the period 

 for their replacing a predecessor arrives, they have not only 

 to move upwards, but also to become erected ; how this 

 is done remains a mystery, for I have been quite unable to 

 discern the means by which it is accomplished. 



When a snake has seized its food, which it retains by 

 means of its many sharp recurved teeth, it slowly swallows 



FIG. 103 (M. 



it by advancing first its lower, then its upper jaw, till it 

 thus, so to speak, forces itself over the body of its prey. 

 When this latter is large, deglutition is a very lengthy 



( J ) One half of the skull of a Python (without the lower jaw) seen from 

 below, a. Intermaxillary bone. 6. Maxillary bone, carrying the outer 

 row of teeth, c. d. Palatine bone and pterygoicl bone, the teeth upon 

 which constitute the inner or second row of teeth. 



