CONTENTS 



Pages 



Some Mineral Relations from the Laboratory Viewpoint. By 



Arthur L. Day - - - - - - - - 141-178 



Bearing of the Tertiary Mountain Belt on the Origin of the 



Earth's Plan. By Frank Bursley Taylor . - - - 179-226 



Isobases of the Algonquin and Iroquois Beaches, and Their Sig- 

 nificance. By James Walter Goldthwait _ - - 227-248 



Cacops, Desmosppndylus ; New Genera of Permian Vertebrates. 



By S. W. WiUiston - - - r - - - , - 249-284 



Migration and Shifting of Devonian Faunas. By Henry S. 



Williams - - 285-2.94 



Persistence of Fluctuating Variations as Illustrated by the Fossil 



Genus Rhipidomella. By Henry S.Williams - - , 295-312 



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