CONTENTS 



Pages 



Pre- Wisconsin Glacial Drift in the Region of Glacier National 



Park, Montana. By William C. Alden and Eugene Stebinger 529-5 72 



Water and Volcanic Activity. By Arthur L. Day and E. S. 



Shepherd 573-606 



Origin of the Bighorn Dolomite of Wyoming. By Eliot Blackwelder 607-624 



Index to "Revision of the Paleozoic Systems." By E. O. Ulrich 625-668 



Abstracts and Discussions of Papers not published in Volume 24. 



E. O. Hovey, Secretary 669-719 



BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Subscription, $10 per year to individuals residing in North America; $7.50 to institutions and 

 libraries and to individuals residing elsewhere than in North America. 



Communications should be addressed to The Geological Society of America, care of 420 1 1 th 

 Street N. W., Washington, D. C, or 77th Street and Central Park, West, New York City. 



NOTICE. — In accordance with the rules established by Council, claims for non- receipt of the 

 preceding part of the Bulletin must be sent to the Secretary of the Society within three months 

 of the date of the receipt of this number in order to be filled gratis. 



Entered as second-class matter in the Post-Office at Washington, D. C. 

 under the Act of Congress of July 16, 1894 



PBESS OF JUDD & DETWEILER, INC., WASHINGTON, D. C. 



\ 





