CONTENTS 



Pages 

 Comparison of American and European Lower Ordovicic Forma- 

 tions. By Amadeus W. Grabau 555-622 



Triassic Igneous Rocks in the Vicinity of Gettysburg, Pennsylvania. 



By George W. Stose and J. Volney Lewis 623-644 



Glacial Lakes and Other Glacial Features of the Central Adiron- 



dacks. By Harold L. Ailing 645-672 



Cretaceous of Alberta, Canada. By Joseph H. Sinclair - - - 673-684 



Triassic Rocks of Alaska. By George C. Martin ----- 685-7 1 8 



Index to Volume 27 - - 719-739 



Title-page, Contents, etcetera, of Volume 27 i-xviii 



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