360 



A MANUAL OF DENTAL ANATOMY. 



The Dinotherium was as large as an elephant, and the 

 downward pointing tusks were about 2 feet in length ; as, 

 however, tusks of only half this length were found in some 

 jaws of identical dimensions and in other respects similar, 

 it is believed that the male Dinotherium had larger tusks 

 than the female. The molar teeth, much like those of a 

 tapir, need not detain us. 



.002 3 



The succession was vertical, as in other mammals, and it 



3 

 had dna. 7 



o 



But the Dinotherium, Mastodon, and Elephant, present 

 us with a very instructive series of modifications in which 

 we see how the excessively complex grinder of the Indian 

 elephant was attained to by degrees. 



The molar of the Dinotherium resembles that of a tapir 

 somewhat; it has not any very great exaggeration of its 

 cusps, and does not deviate very widely from the form of 

 many other mammalian teeth. 



The tooth of Mastodon has its cusps or ridges more 

 numerous and more pronounced, as is seen in the accom- 

 panying figure. 



FIG. 153 



.A. IB 



Other Mastodons have more numerous ridges upon the 

 teeth, and the African elephant has as many as ten upon 



( l ) Molar tooth of Mastodon. 



