CONTENTS 



Pages 



Proceedings of the Thirty-third Annual Meeting of the Geolog- 

 ical Society of America, held at Chicago, Illinois, December 

 28-30,1920. Edmund Otis Hovey, Secretary - - -,- 1-118 



Constitution and By-Laws -- -- 94-100 



Publication Rules 101-104 



Officers, Correspondents, and Fellows of the Society - - _ - 105-118 



Proceedings of the Twelfth Annual Meeting of the Paleontolog- 

 ical Society, held at Chicago, Illinois, December 28-30, 

 1920. R. S. Bassler, Secretary - - 119-156 



Proceedings of the First Annual Meeting of the Society of Eco- 

 nomic Geologists, held at Chicago, Illinois, December 28-29, 

 1920. J. Volney Lewis, Secretary 157-162 



Proceedings of the First Annual Meeting of the Mineralogical 

 Society of America, held at Chicago, Illinois, December 29, 

 1920. Herbert P. Whitlock, Secretary 163-170 



Important Epochs in the History of Petroleum and Natural Gas. 



Presidential Address by L C. White 171-186 



Origin of South American Faunas. Presidential Address by F. B. 



Loomis - - 187-196 



BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



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