' '^ 



CONTENTS 



Pages 



Covey Hill Revisited. By J. W. Spencer 471-476 



Hanging Valleys and Their pre-Glacial Equivalents in New York. 



By J. W. Spencer 477-486 



The Gros Ventre Slide, an Active Earth-flow^. By Eliot Black- 

 welder 487-492 



Geological Reconnaissance in Northeastern Nicaragua. By Oscar 



H. Hershey 493-516 



Some Tertiary and Quaternary Geology of Western Montana, North- 

 ern Idaho, and Eastern Washington. By Oscar H. Hershey. 517-536 



Deflative Scheme of the Geographic Cycle in an Arid Climate. By 



Charles R. Keyes 537-562 



Glaciation in Northwestern Alaska. By Philip S. Smith - - - 563-570 



Stratigraphy of the Coal Fields of Northern Central New Mexico. 



By Willis T. Lee 571-686 



Pre- Wisconsin Glacial Drift in the Region of Glacier National Park, 



Montana. By William C. Alden 687-708 



Mingling of Pleistocene Formations. By B. Shimek - - - . 709-712 

 Toyalane and Lucero; Their Structure and Genetic Relations to 



Other Plateau Plains of Deserts. By Charles R. Keyes - - 713-718 

 Abstracts and Discussions of Papers not published in Volume 23. 



E. O. Hovey, Secretary 719-747 



Index to Volume 23 749-758 



Contents, and Preliminary Pages of Volume 23 i-xvi 



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