CONTENTS 



Pages 

 Proceedings of the Twenty-seventh Annual Meeting of the Geo- 

 logical Society of America, held at Philadelphia, Pennsylvania, 

 December 29, 30, and 3 1 , 1 9 1 4. E. O. Hovey, Secretary - 1-128 



Proceedings of the Fifteenth Annual Meeting of the Cordilleran Sec- 

 tion of the Geological Society of America, held at Seattle, 

 Washington, May 21 and 22, 1914. G. D. Louderback, 

 Secretary 129-140 



Proceedings of the Sixth Annual Meeting of the Paleontological So- 

 ciety, held at Philadelphia, Pennsylvania, December 29, 30, 

 and 31, 1914. R. S. Bassler, Secretary 141-170 



Isostasy and Radioactivity. Presidential Address by George F. 



Becker 171-204 



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