Geol— Vol. I.] SMITH— COMPARATIVE STRATIGRAPHY. 365 



dus -productus Whiteaves, Margarita triassica Whiteaves, 

 Nautilus liardensis Whiteaves, Popanoceras tnacconnelli 

 Whiteaves, Trachyceras canadense Whiteaves, Spiriferina 

 borealis Whiteaves. 



These species probably represent both Tirolic and Baju- 

 varic faunas, but the information is at present too meager 

 for one to assign them to anything more definite than the 

 Upper Trias in general. All the information available and 

 figures and descriptions of all these species have been pub- 

 lished by Dr. J. F. Whiteaves (42). 



But little is known concerning the Trias of Alaska, 

 fossils of that age having been found at but few places. 

 Dr. Paul Fischer (8) has described the occurrence of 

 Monotis shales on the shores of the Peninsula of Alaska, 

 but it is quite probable that the forms referred to belong 

 rather to Pseudomonotis. Dr. C. W. Hayes (12) discovered 

 in the St. Elias Range some black shales, containing Pseu- 

 domonotis conf. subcircularis Gabb. These occurrences 

 make it reasonably certain that the Upper Trias extended 

 from British Columbia through Alaska into northeastern 

 Siberia, for the Pseudo7nonotis fauna is found in all these 

 regions. 



General Discussion and Summary of the 

 American Trias. 



The entire Triassic column is now known to be repre- 

 sented in the United States, although only parts of it in any 

 one locality. While the areal distribution of Marine Trias 

 in America is small, the richness of the faunas compares 

 favorably with that of formations that cover the greater part 

 of the surface of the continent. 



Marine faunas of Lower Triassic age are now known 

 only in the Meekoceras beds of the Aspen Mountains of 

 southeastern Idaho and in the Inyo Range of California, 

 where the faunas are very similar and belong to the Brah- 

 manic and possibly the lower Jakutic stages. The most 

 characteristic genera in these two localities are Meekoceras, 



