412 



DEVONIAN PERIOD 



Fig. 362. Sketch map of Europe during the Devonian. The horizontal lines 

 represent the Lower Devonian; the vertical lines mark the additional areas where 

 the Middle Devonian occurs. (After De Lapparent.) 



In the Devonian of Germany much igneous rock is interbedded 

 with the sedimentary. The igneous rock occurs in many separate 

 beds, showing that there were many periods of igneous activity 

 separated by intervals of quiet. In not a few places, especially 

 where the sedimentary rocks have been invaded by igneous rocks, 

 mineral veins have been developed, and from them large quantities 

 of iron, tin, copper, and other metals have been obtained. 



The Devonian of Russia is made up of beds of arenaceous and 

 calcareous rocks, the former containing fossils related to those of 

 the Old Red Sandstone, the latter containing fossils of a marine 

 fauna. The Lower Devonian appears to be wanting in much of 

 Russia, and the Middle and Upper parts of the system are in most 

 places unconformable on subjacent formations. 



Other continents. The Devonian system has wide distribu- 

 tion in Siberia and China, and is known at many points in southern 

 Asia. It occurs in North and South Africa, in New South Wales, 



