32 



osborn: OLIGOCENE, MIOCENE, pliocene equid^e. 



Elephas imperator-Equus excelsus Zone, Lower Pleistocene. Sicilian, Cromerian, or St. Prestian op Europe. 



The E. imperator zone (Osborn, 1909) does not appear to be distinguished from the Equus beds (Cope), Lower 

 Pleistocene (W. D. M., 1916). 



1. Typical Loup River beds, Loup Fork of Platte, Meek and Hayden, 1861, 1862. 

 2. Horizon F (upper part only), Hayden and Leidy, 1869. 



4. Equus (E. excelsus) beds, Cope. 



5. Sheridan beds, Scott. 



3. Several formations (unnamed) in Texas and Mexico, containing Elephas imperator. 

 6. Elephas imperator zone, Osborn, 1909. 



Fig. 15. Regions of the Alachua Clays (Lower Pliocene) and Peace Creek (Upper Pliocene) deposits of 

 Florida. After Osborn, 1910. 



Of the specimens collected in the typical Loup River beds Leidy recorded in 1869 the following: Elephas imperator 

 Mastodon (Dibelodon) mirificus, Equus excelsus. The type of Equus excelsus is elsewhere stated to be from the "Pawnee 

 Loup branch of the Platte or Niobrara River." This indicates a slightly different faunal phase than that of the typical 

 Equus beds or zone of Cope. The E. excelsus type of Leidy is slightly similar in crown pattern to Merriam's Pliohippus 

 provcrsus of the Upper Etchegoin. 



Type of Equus excelsus Leidy, 1858. 



