THE EOCENE PERIOD. 



249 



At the time of its maximum extension (Middle Oligocene, Fig. 438), the 

 epicontinental sea of the period covered much of north Germany, and 

 the North Sea was connected with the Mediterranean, and extended to 

 southeastern Russia, and even to the Aral sea. 1 



The oldest Oligocene deposits of central and western Europe are 



largely of terrestrial, fresh- and brackish-water 



Local de- 



Fig. 438. — Sketch-map of Europe in the Middle Oligocene. The shaded part shows 

 area of deposition. (After De Lapparent.) 



posits of salt and gypsum show that there were local bodies of water of 

 excessive salinity. 



In Britain, the Oligocene has but slight representation, being found 

 in one small area (Hampshire basin and Isle of Wight) only. As in 

 most other parts of Europe, the beds are partly marine and partly non- 

 marine. Some of the igneous rocks of the islands about north Scotland 

 may have dated from this period. The Oligocene is represented in the 

 Paris basin, partly by marine beds, partly by beds deposited in brack- 



1 Kayser, Geologische Formationskunde, p. 479. 



