AGE OF GYPSUM OF CENTRAL IOWA 



731 



FOREIGN. 



AMERICAN. 



PLEISTOCENE AND RECENT. 



Caspian Sea and Asiatic lakes. ^ | Great Salt Lake. 



PLIOCENE. 



Transylvania, near Prague (salt).^ 

 Caspian Sea in Karabhogas Bay 



(salt and gypsum).3 

 Austria at Wieliczka, Siebenbiirgen 



(salt and gypsum).'' 



MIOCENE. 



None. 



OLIGOCENE. 



Transylvania and Carpathian Moun- 

 tains (gypsum and salt).5 

 Germany, Sperenberg (gypsum).® 

 France, Montmartre (gypsum).'' 



EOCENE. 



None. 



CRETACEOUS. 



None. 



JURASSIC. 



None. 



TRIASSIC. 



Germany:^ Black Hills (gypsum). 



Hanover, Arnstadt. 



Erfurt, Thuringia. 



Lothringen (gypsum and salt). 

 England :' 



From Scotland to Devonshire 

 (gypsum and salt). 



'Geikie, Text-Book of Geology, 3d ed., pp. 737-39- 



^ Ibid., p. 1 018. 



'^ Ibid., p. 1004. 



^Credner, Geologic, pp. 699, 700. 



sGeikie, op. cit., p. 993. 



*Credner, op. cit., p. 679. 

 T Ibid., p. 675. 

 ^ Ibid., p. 520. 

 'Geikie, op. cit., p. 866. 



'°U. S. Geological Survey, Barton's report on Black Hills, Twenty-first Annual 

 Report, Part IV. 



