CONTENTS 



Pages 



Close of Jurassic and Opening of Cretaceous Time In North Amer- 

 ica. By Henry Fairfield Osborn --- 295-302 



Reasons for Regarding the Morrison an Introductory Cretaceous 



Formation. By Willis T. Lee 303-314 



Origin and Distribution of the Morrison Formation. By Charles C. 



Mook 315-322 



Sauropoda and Stegosauria of the Morrison of North America Com- 

 pared with Those of Europe and Eastern Africa. By Richard 

 Swann Lull 323-334 



Paleobotanic Evidence of the Age of the Morrison Formation. By 



Edward Wilber Berry 335-342 



Invertebrate Fauna of the Morrison Formation. By T. W. Stanton. 343-348 



Studies of the Morphology and Histology of the Trepostomata or 



Monticuliporoids. By E. R. Cumings and J. J. Galloway - - 349-374 



Present Condition of the Volcanoes of Southern Italy. By H. S. 



Washington and Arthur L. Day 375-388 



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