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A MANUAL OF DENTAL ANATOMY. 



wards, and sharply pointed ; as they iriterdigitate with one 

 another there is very little wear upon the points, which 

 consequently remain quite sharp. The largest teeth are 

 those situated about the middle of the dental series. 



FIG. 131 (i). 



Many variations in the number and form of the teeth 

 are met with ; the porpoise has not more than half the 



FIG. 132 ( 2 ) 



number of teeth possessed by the dolphin, while the gram- 

 pus has still fewer. The teeth of the grampus become 

 worn down on their opposed surfaces, and coincidently 

 with their wearing away the pulps become calcined. In 

 the Oxford museum there is a grampus in which, owing to 

 a distortion of the lower jaw, the teeth, instead of inter- 

 digitating, became exactly opposed to one another ; the 

 consequence of this was that the rate of wear was greatly 

 increased, and the pulp cavities were opened before the 



(*) Jaws of a common Dolphin. 



( 2 ) Teeth of upper jaw of a Grampus (after Professor Flower). 



