TLbc S^ournal of 0eolOGi? 



Vol. XXIII CONTENTS FOR JANUARY-FEBRUARY J9J5 No. i 



THE ORIGIN OF THE INCLUSIONS IN DIKES Sidney Powers i 



THE MIDDLE AND UPPER DEVONIAN OF THE ROMNEY, WEST VIRGINIA, REGION 



Charles S. Prosser ii 



THE STRENGTH OF THE EARTH'S CRUST. VII. VARIATIONS OF STRENGTH WITH DEPTH AS 



SHOWN BY THE NATURE OF DEPARTURES FROM ISOSTASY (Section B) - - Joseph Barrell 27 



SOME ELLIPSOIDAL LAVAS ON PRINCE WILLIAM SOUND, ALASKA S. R. Capps 45 



A SKETCH OF THE LATE TERTIARY HISTORY OF THE UPPER MISSOURI RIVER 



Clyde Maxwell Bauer 52 



THE INTER GLACIAL GORGES OF SIX MILE CREEK AT ITHACA, NEW YORK 



John Lyon Rich and Edwin A. Filmer 59 



SUMMARIES OF PRE-CAMBRIAN LITERATURE OF NORTH AMERICA FOR 1909, 1910, igii, AND PART 



OF 191 2 ---.------------- Edward Steidtmann 81 



REVIEWS 92 



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