658 NORTH AMERICAN INDEX FOSSILS. 



sent this series in part. In southeastern Alaska and the Yukon 

 region, the Kenai series of sandstones, conglomerates, shales and 

 coals (sometimes called Oligocenic) represents this horizon while 

 the Gakona group and the Cantwell formation represents this 

 horizon in other parts of Alaska. 



In Greenland, the Atane or Atanekerdluk leaf beds belong to the 

 Lower Eocenic. 



In the interior of the continent of North America, the Tertiary 

 beds are represented by continental deposits, chiefly fluviatile, 

 or eolian, more rarely by beds of lacustrine origin. The Eocenic 

 is represented in descending order as follows : 



IV. Upper Eocenic : the Uinta beds of Utah. 

 All of these overlap more or less.^^ 



III. Middle Eocenic: the Green River bed (2,000 ft.); 

 Bridger beds (1,800 ft.) and Washakie beds of Wyo- 

 ming. 

 11. Lower Eocenic: the Wasatch formation (2,500 ft.) of 

 the Bighorn Basin, Wyoming; the Knight formation of 

 Evanston, Wyoming (1,750 ft.) ; the Wind River beds 

 of Wyoming (partly Middle Eocenic) (1,700 ft.) and 

 the Huerfano beds of Colorado (800 ft.). 

 I. Basal Eocenic: including the Fort Union of Montana 

 and the Puerco and Torrejon of New Mexico (850 ft.). 



XIII. The Oligocenic System. 



This is typically developed in the Gulf coast region, where the 

 following divisions are recognized :^^ 



Upper Oligocenic. 

 Alum Bluff beds. 

 Oak Grove beds. 



Middle Oligogenic or Chipolan. 



Chipola marls. 

 Chattahoochee beds. 



^^ See Bull. 361, U. S. Geo!. Survey, p. 22,. 

 *^ Maury, C. J., Bull. Am. Pal, III., p. 391. 



