FORMATIONS AND PHYSICAL HISTORY 563 



tlu- Meso/oie era. Later, but still early in the Eocene, submergence 

 set in, allowing the sea to cover considerable areas from which it 

 had been excluded temporarily. In western and central Europe the 

 maximum submergence of the Eocene seems to have been accom- 

 plished by the middle of the period. Toward its close, the epiconti- 

 lu-ntal waters of the northwestern part of the continent were again 

 restricted. 



In the south, the Eocene sea spread much beyond the borders 

 of the present Mediterranean, covering much of southern Europe 

 and northern Africa. Eastward it joined the Indian Ocean, cut- 

 ting off the southern peninsulas of Asia from the mainland to the 

 north. A sound east of the Urals 

 probably connected the Arctic Ocean 

 with the expanded Mediterranean. 

 Above this sea rose many islands, 

 some of which corresponded in 

 position to the Alps, Carpathians, 

 Apennines, and Pyrenees. 



On the bottom of this great body 



of water, limestone was deposited .... 



. Fig. 475. A bit of nummulilic 

 on an extensive scale. Much of limestone. 



it is made up almost wholly of the 



shells of nummulites (foraminifera, Fig. 475), and is found from 

 one side of the Old World to the other. Since it is thick 

 (locally several thousand feet) as well as widespread, the sea must 

 have swarmed with foraminifera, and the period must have been 

 long. In few other places are there indications of such great num- 

 bers of organisms of one kind. Some idea of the deformative move- 

 ments since the Eocene may be gained from the fact that the num- 

 mulitic limestone occurs at elevations of more than 10,000 feet in 

 the Alps, up to 16,000 feet in the Himalayas, and 20,000 feet in Tibet. 

 In the Old World as well as in the New, the greater relief features of 

 the present are post-Eocene. 



Other continents. Marine Eocene is known along the northern 

 and western coasts of Africa, and in the Soudan, in South Australia, 

 New Zealand, and Tasmania, and in various islands of the Pacific. 

 The Tertiary formations of South America have not been closely 

 correlated with those of other continents. There is marine Eocene 

 along some parts of the western coast, in Patagonia 1 (Magellanian 



1 Hatcher, Am. Jour. Sci., Vol. IV, 1897, p. 334, and Vol. IX, 1900, p. 97. 



