PLEISTOCENE OF EUROPE, NORTH AFRICA, AND NORTH AMERICA 439 



I. First or Equus-Mylodon Zone of the Plains regions (see p. 452). 

 Mammals of this period include among surviving forms, machaerodonts, 

 camels (llamas), mylodont sloths, prong-horn antelopes, white-tailed deer, 

 and numerous horses. The glyptodonts survive in the south. The mas- 

 todons no longer appear in the Great Plains region. The giant dogs, or 



Fig. 189. — Distribution of the Proboscidea in North America. (After Lucas). A. Ele- 

 phas imperator, the imperial mammoth. B. Elephas columbi, the Columbian mammoth. 

 C. Elephas primigenius, the northern mammoth. D. Mastodon americanus, the American 

 mastodon. 



dinocyons, appear to survive. The peccaries are represented by Platy- 

 gonus. Among the newly appearing forms are the giant beavers (Casto- 

 roides) and the badgers (Taxidea). In this assemblage there are no true 

 European deer (Cervus), no bison, no bear, and no mountain goats 

 (Oreamnos) nor mountain sheep (Ovis), and since it is largely a temperate 

 fauna, there are no reindeer nor musk oxen. 



II. Second or Megalonyx Zone (see p. 464). The mammals of this 

 stage, which are believed to belong to the temperate and favoral)le inter- 

 glacial zones of mid-Pleistocene times and to the south bc^yond glacial in- 



