CONTENTS 



Pages 



Observations on the Mode of Life of Primitive Cephalopods. By 



Rudolf Ruedemann - . - . 315-320 



Status of Our Knowledge of Mesozoic Pathology. By Roy L. 



Moodie - - ,- 321-326 



Evolution, Phylogeny, and Classification of the Mastodontoidea. 



By Henry Fairfield Osborn 327-332 



Criteria for the Determination of the Climatic Environment of 



Extinct Animals. By E. C. Case -- 333-338 



Methods of Determining the Relationships of Marine Invertebrate 



Fossil Faunas. By Charles Schuchert 339-348 



Criteria for Species, Phylogenies, and Faunas of Trilobites. By 



Percy E. Raymond 349-352 



Criteria for Determination of Climate by Means of Fossil Plants. 



By F. H. Knowlton - - 353-358 



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