LIFE 591 



faunas of this region are strikingly similar to the Miocene and later 

 faunas of Australia and New Zealand. 



Arctic latitudes and climate. Miocene beds are somewhat 

 widely distributed in the Arctic regions and seem to be largely of 

 terrestrial origin, with fossil floras indicating a warm temperate 

 climate. 



LIFE 



Land Plants 



The mid-latitude flora of the Miocene records the gradual dis- 

 appearance of subtropical types, and an increase of deciduous trees. 

 This is particularly true of North America, where the flora came to 

 resemble that of to-day in somewhat lower latitudes, and is indeed 

 its predecessor. An important feature in North America was an 

 increase in the grasses, with its appropriate effect on mammals. 



Land Animals 



Earlier fauna. The early Miocene land fauna of North America 

 was very distinct from the late Miocene. The former resembled 



Fig. 496. A Miocene Mastodon, Tetrabelodon angustidens Cuvier. (Restora- 

 tion by Gaudry.) 



the Oligocene (White River) fauna. True carnivores, chiefly of the 

 cat and dog families, had succeeded the primitive forms. Several 

 branches of the perissodactyls had disappeared, reducing them 



