218 ANIMALS OF THE PAST 



bany, N. Y. ; Field Columbian Museum, Chicago ; Car- 

 negie Museum, Pittsburgh Museum of Comparative 

 Zoology, Cambridge, Mass. There is no mounted skele- 

 ton in the United States National Museum, nor has there 

 ever been. 



The heaviest pair of tusks is in the possession of T. O. 

 Tuttle, Seneca, Mich., and they are nine and one-half 

 inches in diameter, and a little over eight feet long; 

 very few tusks, however, reach eight inches in diameter. 

 The thigh-bone of an old male mastodon measures from 

 forty-Jive to forty-six and one-half inches long, the hu- 

 mer us from thirty-Jive to forty inches. The height of 

 the mounted skeleton is of little value as an indication of 

 size, since it depends so much upon the manner in which 

 the skeleton is mounted. The grinders of the mastodon 

 have three cross ridges, save the last, which has four, and 

 a Jinal elevation, or heel. This does not apply to the 

 teeth of very young animals. The presence or absence 

 of the last grinder will show whether or not the animal is 

 of full age and size, while the amount of wear indicates 

 the comparative age of the specimen. 



The skeleton of the " Warren Mastodon " is described 

 at length by Dr. J. C. Warren, in a quarto volume en- 

 titled " Mastodon Giganteus." There is much informa- 

 tion in a little book by J. P. MacLean, " Mastodon, 

 Mammoth, and Man," but the reader must not accept all 

 its statements unhesitatingly. The Jirst volume, 1887, 



