Ch. X.] 



TEETH OF EXTIXCT MAMMALIA. 



135 



of the three species of elephants, figs. 112 a, 113, 114, it will be seen 

 that the folds of enamel are most numerous in the mammoth, fewer 

 and wider, or more open, in E. antiquus, and most open and fewest 

 in E. meridimalis. It will be also seen that the enamel in the molar 

 of the rhinoceros tichorhinus (fig. 116) is mnch thicker than in that 

 of the rhinoceros leptorhinus (fig. 115). 



Fis. 120. 



Fig. 121. 



Deer. 



Elk {Oermts aloes, L.); re- 

 cent; molar of upper jaw. 



a. Grinding surface. 

 &. Side view ; two-thirds of 

 nat. size. 



c, d. Ox. 



Ox, common, from shell-marl, Forfar- 

 shire; true molar, upper jaw; two- 

 thirds nat. size. Recent. 



c. Grinding surface. 



d. Side view; fangs uppermost. 



Fig. 122. 



Fig. 123. 



a. Canine tooth or tusk of bear ( Ur-sv.s 



spelceus) ; from cave near Liege. 



b. Molar of left side, upper jaw; one- 



third of nat. size. Post-pliocene. 



Tiger. 



c. Canine tooth of tiger (Felis tigris) ; re- 



cent. 



d. Outside view of posterior molar, lower 



jaw; one-third of nat. size ; recent. 



Fig. 124 



Hymna spelcea ; lower jaw. Kent's Hole, Torquay, Devonshire. 

 One-third nat. size. Post-pliocene. 



