DESCRIPTIONS OF REMAINS OF VERTEBRATA FROM TERTIARY 

 FORMATIONS OF DIFFERENT STATES AND TERRITORIES 

 WEST OF THE MISSISSIPPI RIVER. 



The fossil remains described in the succeeding pages consist mainl\' of 

 isolated specimens obtained from Tertiary formations in various parts of the 

 country west of the Mississippi River. They are nearly all remains of mam- 

 mals. Included in the series there are descriptions of a few other Tertiary 

 mammalian fossils, from the country east pf the Mississippi, described on 

 account of their relation with the former, and for the most part for the first 

 time. 



MAMMALIA. 



Order Carnivora. 

 FELIS. 



FeLIS AUC4USTUS. 



Several teeth in fragments of jaws, and portions of other teeth, indicate a 

 sjjecies of tiger apparently diiferent from any previously described. The 

 specimens were discovered by Professor Hayden, during Warren's expedition 

 of 1857, on the Loup Fork of the Niobrara Eiver, iSTebraska. They belong 

 to the Pliocene Tertiary formation, and were found in association with remains 

 of Mastodon mirificus, Merychyus elegans, Frocamelus occidcHtalis, &^'c. 



The most characteristic of the specimens, represented in Fig. 19, Plate VII, 

 is an upper sectorial molar contained in a small jaw-fragment. The tooth is 

 about the size of that of the Bengal tiger, and is therefore too large to have 

 belonged either to the panther or the jaguar. It is as much too small to 

 have belonged to the extinct American lion, or Felis atrox, as its l)Veadth is 

 but little greater than the sectorial molar contained in tlie lower jaw from 

 which the latter was described. The form of the tooth is the same as in the 

 American panther and Bengal tiger. The breadth of the crown is slightly 

 less, and its thickness proportionately greater than in the corresponding teeth 

 of a skull of the latter with which the fossil was compared. 



