THE JURASSIC PERIOD. 77 



Throughout much of western Europe, the Jurassic beds are still 

 nearly horizontal, but in the Jura Mountains, in the Alps, and other 

 mountains of the south central system of Europe, as well as in the 

 Caucasus, they are tilted and sometimes closely folded. Where they 

 have been undisturbed they are often unindurated. In the eastern 

 province the deformation of the beds is not great. 



Extra-European Jurassic. 



Arctic lands. — The Upper Jurassic formation is found in Spitz- 

 bergen, Nova Zembla, Franz Josef Land (Russian type of fauna), 

 over a large part of Siberia, and in the New Siberian Islands to the 

 north, in the Aleutian Islands which form the connecting link between 

 Asia and America, in Alaska, in some of the Arctic Islands of North 

 America, and in eastern Greenland. This distribution means a great 

 Arctic Sea in the Late Jurassic epoch, with two considerable dependen- 

 cies to the south — the one in Russia, the other, as we have already 

 seen in western North America. In all of the high latitudes where 

 the L T pper Jurassic strata are widely distributed, the Lower Jura is 

 wanting, as far as known, and in most of them the Brown Jura 

 also. 



Asia. — The Lias is not known in central Asia, but it occurs in Asia 

 Minor, north Persia, Assyria, the Himalayas, and Japan. 1 The Middle 

 Jura, largely clastic and of terrestrial origin, is wide-spread in northern 

 Asia, some beds containing much carbonaceous matter. Marine Middle 

 Jura is known in northern India. 2 The tapper Jura is known at vari- 

 ous points in Asia Minor, in the Himalayas, in Tien Shan, Japan, and 

 Siberia. It covers great areas in the basins of the Olensk, the Lena, 

 the Jana, the Yenesei, and the Obi Rivers, 3 and in Kamtschatka, but 

 is not known in central Asia. The Jurassic strata, especially the 

 Upper Jurassic, are therefore widely distributed in Asia as in Europe. 



Africa. — So far as now known, the marine Jurassic of this con- 

 tinent is confined to the northern and eastern coasts. Marine Lias is 

 known only in Algeria and western Madagascar; the middle and upper 

 parts of the system occur both in the north and in the southeast. 

 The western coast of India and the eastern coast of Africa, including 



1 De Lapparent, op. cit., pp. 1084 and 1101. 



2 Idem, p. 1142. 



3 Idem, p. 1233. 



