CHAPTER V 

 DENTITION 



IN the most generalized snakes — those which 

 show the nearest approach to lizards — teeth are 

 present not only on the rami of both jaws, but also 

 on the premaxillary bone, on the palatines, and on 

 the pterygoids. A reduction of the dentition takes 

 place in various genera, in which the teeth of either 

 the upper or the lower jaw, and of the palatines or 

 pterygoids, or both, may be absent, and the pre- 

 maxillary is devoid of teeth in the great majority, 

 including all European representatives, of the Ophidia. 

 In the egg-eating snakes of the genera Dasypeltis 

 and Elachistodon the dentition is very much reduced, 

 in accordance with the peculiar regime, and this 

 deficiency is compensated by the development on 

 some of the anterior thoracic vertebras of long, tooth- 

 like processes (hypapophyses) directed forwards, and 

 capped with a remarkably dense, vitreous tissue 

 simulating enamel, the function of these tooth-like 

 processes being to break the shell of the egg within 

 the gullet, where none of its contents are lost, the 

 shell being afterwards rejected through the mouth in 

 the form of a pellet. 



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