216 



GEOLOGY 



the Cretaceous beds were deeply eroded before the deposition of the 

 overlying Eocene. The break between the Cretaceous and the Eocene 

 was long regarded as one of the great breaks in the geological record, 

 but the hiatus is partially and imperfectly bridged by the estuarinc, 

 lacustrine, and other deposits of the Early Eocene. It is not to be 



%3 



X 1% 



Fig. 425. — Sketch-map of Europe, during the Eocene, Lutetian stage. The shaded 

 portions represent areas of deposition. (After De Lapparent.) 



lost sight of that the one period merged insensibly into the next, even 

 though the strata which recorded the transition may not be found 

 in every region. In southern Europe, the separation of Cretaceous 

 and Eocene is much less sharp, showing that the notable geographic 

 changes of the western region did not affect the southern and south- 

 eastern parts of the continent, or at least not to the same extent. 



To the early Eocene lakes, estuaries, and other sites of deposition, 

 in western Europe, and later to the sea which covered a part of the 

 same area, considerable streams flowed from the surrounding lands. 

 Into the arm of the sea which covered parts of England, France, and 



