THE COMPARATIVE STRATIGRAPHY OF THE 

 MARINE TRIAS OF WESTERN AMERICA. 



BY JAMES PERRIN SMITH. 



CONTENTS. 

 Plates XL-XLIX. 



Page 



Preface 323 



The Geography of the Trias 326 



The Mediterranean Region 327 



The Oriental Region 329 



The Arctic-Pacific Region 331 



The American Region 332 



The Subdivisions of the Trias 333 



Interregional Correlation Table of the Trias 



The Lower Trias or Scythic Series 334 



The Brahmanic Stage 334 



The Jakutic Stage 336 



The Middle Trias or Dinaric Series 338 



The Upper Trias 340 



The Tirolic Series 340 



The Bajuvaric Series 342 



The Trias of North America 343 



Historical 343 



The Geography of the Trias in America 346 



The Lower Trias 348 



The Lower Trias of Idaho 348 



The Lower Trias of California 350 



The Middle Trias 352 



The Muschelkalk of Nevada 352 



The Middle Trias of California 356 



The Upper Trias 358 



The Upper Trias of Plumas County^ California . . 358 



The Upper Trias of Shasta County^ California. . . 359 



The Humboldt Range 363 



The Upper Trias of British Columbia and Alaska.. 364 



General Discussion and Summary of the American Trias 365 



Descriptions of the Species 367 



Bibliography 409 



Explanation of Plates 412 



[325] 



