366 IVORY AND THE ELEPHANT 



long memoir by Dr. J. C. Warren of Boston,* and now in 

 the American Museum of Natural History. Another noted 

 locality is near St. Louis, Missouri, whence came a fine 

 skeleton now in the British Museum; and in more recent 

 years numerous skeletons, skulls, and teeth have been dis- 

 covered in the draining of swamps and peat bogs in Ohio, 

 Indiana, Illinois, Michigan, Iowa, and other States. Prac- 

 tically all these finds are in post-glacial deposits, and the 

 absence of mastodon remains in the northern New England 

 States and eastern Canada is perhaps explained on the sup- 

 position that these regions were still buried in glacial ice 

 at the time of the final extinction of the mastodon and mam- 

 moth. 



Recently the fossil deposits of Nebraska have supplied 

 a great wealth of specimens illustrating the development 

 of mastodon and mammoth in North America. It is said 

 that this State can boast of nearly two hundred miles of 

 mastodon beds, extending from Knox County to Sioux 

 County. The great variety of forms represented is shown 

 by the fact that six species of mastodons and four species 

 of mammoths are represented. One exceptionally fine 

 mastodon skeleton was discovered in Cherry County, and 

 this is perhaps the finest fossil mastodon in the world. f 



In the development of the elephant from its ancestral 

 types, the evolution of the proboscis has followed the length- 

 ening of the tusks. In the very earliest forms, such as 

 the Mceritherium for instance, tusks and proboscis are 

 only beginning to exhibit the characteristics peculiar to the 

 Proboscidea, but in later forms, when the tusks — in this 

 stage four in num^^*, two in the upper and two in the lower 



*J. C. Warren, 1885, " Description of a Skeleton of the Mastodon Giganteus of North 

 America." 



fErwin H. Barbour, "Prehistoric Elephants in the Morrill Collections, the Nebraska 

 State Museum and the University of Nebraska," Sunday State Journal, Omaha, January 3, 

 1915. 



