CONTENTS 



Pages 

 Problems of the Interpretation of Sedimentary Rocks. By A. W. 



Grabau - 735-744 



Rhythms and the Measurements of Geologic Time. By Joseph 



Barren 745-904 



Diagnostic Characteristics of Marine Clastics. By E. M. Kindle. 905-9 1 6 



Characteristics of Continental Clastics and Chemical Deposits. 



By Eliot Blackwelder - - - - 917-924 



Significance of Sorting in Sedimentary Rocks. By Eugene W. 



Shaw ------ , - - 925-932 



Chemical and Organic Deposits of the Sea. By Thomas Way- 

 land Vaughan 933-944 



Stratigraphic Relationships of the Tully Limestone and the Gen- 

 esee Shale in Eastern North America. By A. W. Grabau. 945-958 



Were the Graptolite Shales, as a Rule, Deep or Shallow Water 



Deposits? By A. W. Grabau and Marjorie O'Connell - 959-964 



Geologic Significance of Fossil Rock-boring Animals. By Albert 



L. Barrows - - '- 965-972 



Second Report of the Committee on the Nomenclature of the 

 Cranial Elements in the Permian Tetrapoda. By William 

 K. Gregory, Secretary. With Appendices by R. Broom, 

 D. M. S. Watson, and S. W. Williston - 973-986 



Index to Volume 28 - - - 987-1005 



Title-page, Contents, etcetera, of Volume 28 i-xxii 



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