THE EOCENE PERIOD. 251 



and coal. Locally, the beds are now nearly vertical, and their disturb- 

 ance, accompanied by great outpourings of lava, seems to have begun 

 before the close of the Oligocene period. About the Dardanelles, the 

 Oligocene is non-marine, and coal-bearirg. 1 Farther south, the system 

 is not all marine. Among the non-marine formations is coal. The 

 fossils of southern Europe indicate some such climatic conditions as 

 those of the Mexican Gulf coast at the present time. 



In Europe, as in North America, there were considerable igneous 

 eruptions during the Tertiary, and especially during the Oligocene. The 

 results are to be seen in Bohemia, where there is much igneous rock, 

 and in northern Ireland and western Scotland, where outpourings of 

 lava probably made great plateaus, of which some of the adjacent 

 islands are remnants, in Iceland, and in the Vienna basin. Between 

 eruptions, vegetation grew in the marshes and shallow lakes and over 

 the surface of the lava. The substance of this vegetation is locally 

 (Faroes, and Iceland) preserved in the form of coal between the lava- 

 beds. Some of the lakes of France seem to have been obliterated by 

 volcanic action. 



Amber. — One of the peculiar formations found in the Lower Oligo- 

 cene is the amber of northern Germany. This is found principally in 

 the vicinity of Konigsberg. AVhile amber in small quantities is found 

 in Sicily and a few other places, that of the Baltic region is more abun- 

 dant than that of any other part of the earth, so far as now known. 

 Amber is fossilized resin, apparently from certain varieties of coniferous 

 trees. Its oiiginal position in the Baltic region appears to be in certain 

 glauconitic beds of a clayey nature, but parts of this formation have 

 been worn by the waves, and the amber distributed. Some of that 

 which finds its way into commerce is picked up on the Baltic shore, 

 while some is taken from the beds in which it was originally entombed. 



One of the interesting features of the amber is the fact that it fre- 

 quently contains insects. The insects seem to have alighted upon the 

 resin while it was soft, and to have become completely immersed in it, 

 and perfectly preserved. About 2000 species have been found thus 

 entombed. Subsequently, by the escape of its volatile portions, the 

 resin became hard, and was ultimately changed to amber. The amber 

 of the Baltic region was known to the Phcenicians, who appear to have 

 made trips to the region for it. 



1 English, Q. J. G. S., 1904, p. 246. 



