212 B. S. Lull— Evolution of the Elephant. 



Fig. IT. Last upper molar, tooth of Tetrabelodon angustidens. Catalogue 



No. 11732 Yale Museum, 1/4 natural size. Original. 

 Fig. 18. Skull of Dibelodon andium, modified from Burmeister. 

 Fig. 19. Skull of Mammut americanum. Original. 

 Fig. 20. Last upper molar tooth of Mammut americanum. Catalogue No. 



10681 Yale Museum, 1/4 natural size. Original. 

 Fig. 21. Restoration of the American mastodon, Mammut americanum, 



after Marsh, 1/32 natural size. The animal stands too high at the 



shoulders and the tusks are reversed, as they should curve inward 



at the tip. Catalogue No. 12600 Yale Museum. 

 Fig. 22. Molar tooth of Stegodon clifti. From a cast, No. 10759, Yale 



Museum, 1/4 natural size. Original. 

 Fig. 23. Molar tooth of Elephas imperator. Catalogue No. 11677, Yale 



Museum, 1/4 natural size. Original. 

 Fig. 24. Molar tooth of Elephas columbi. Catalogue No. 11683, 1/4 



natural size. Original. 

 Fig. 25. Molar tooth of the mammoth Elephas primigenius ; after Marsh. 

 Fig. 26. Mammoth found in the Lena Delta, Siberia, in 1799, as mounted 



in the St. Petersburg Zoological Museum. Portions of the hide 



still adhere to the head and feet ; after Marsh. 

 Fig. 27. Jaw of Dinotherium, showing the downwardly directed lower 



tusks ; after Kaup. 



