CONTENTS 



Prefatory note 5 



Introduction .......... 6 



Chapter 1 



Stratigraphic structure of Becraft mountain .... 6 

 Chapter 2 



Description of the fauna 16 



Vertical range of species . 65 



Faunal values of species 68 



Chapter 3 



Nature and distribution of the Oriskany fauna in New York 72 



Distribution of the calcareous facies 72 



Ulster county , 72 



Orange county ......... 75 



Albany and Schoharie counties 77 



The original Oriskany sandstone 78 



Fauna of the Gaspe limestones ...... 80 



Chapter 4 



The Devonic age of the Helderbergian fauna and the base 



of the Devonic system in New York .... 82 



1 the argument from correlation ..... 83 



2 the argument from the intrinsic character of the fauna 83 



3 the argument from stratigraphy ^95 



Fauna of the Manlius limestone . . ... * 98 



Explanation of plates 103 



Index ,122 



