South Dakota School of Mines Bulletin Xo. 13. Plate No. 12. 



A. Restoration of head of the Titanothere Megacerops. Lull, 1905. 



B. Outline restoration of head of the Saber-tooth tiger, Smilodon, to 

 show the wide open jaw and the opportunity the animal had of us- 

 ing the great canine fangs for stabbing and ripping its prey. 

 Matthew, 1905. 



