I go 



Era 



TIEREDITV AND E\(ILU'1I(IN IN PLANTS 



Table II. — Table of Geological Time 



Period 



133. Paleogeography. — By changes in the relative level 

 of the land and sea, above referred to, rocks contain- 

 ing fossils may be elevated as dry land, and frequently 

 as mountains, so that remains of marine organisms, as 

 well as of others, are often found at high elevations. In 

 some cases forests near the seashore have been submerged, 

 and covered over with sediment, then elevated again as 

 dry land, so that subsequent excavations have revealed 

 the fossilized trunks and stumps (Figs. 83 and 84). Thus 



