Geol— Vol. I.] SMITH— COMPARATIVE STRATIGRAPHY. 343 



Spiti. In California the upper part of the Hosselkus 

 limestone and the shales above them contain certain genera 

 that seem to be confined to the Noric horizon, especially 

 Halorites, Rhahdoceras, and Pseudonionotis subct?'cularis, 

 the American representative of the Arctic-Pacific Pseu- 

 domonotis ochotica, which is found in Siberia, Alaska, Peru, 

 and the Indian Archipelago. 



The Rhaetic, or upper division of the Bajuvaric, is not 

 represented by interregional faunas, and its marine equiv- 

 alents have not been identified outside the Mediterranean 

 region. 



Marine faunas of Upper Triassic age have been described 

 in monographic form from the Mediterranean region by 

 E. von Mojsisovics (21-23) ; from the Arctic-Pacific region 

 by the same author (20) ; from the Oriental region also by 

 Mojsisovics (24), and by A. von Krafft (15), who has given 

 preliminary lists of species of which descriptions are prom- 

 ised at an early date ; from the American region by W. M. 

 Gabb (9), by A. Hyatt (13) in the form of preliminary 

 lists, and by J. P. Smith (31) ; and from the Canadian prov- 

 ince by J. F. Whiteaves (42). The reptilian fauna of the 

 American Trias has been described by Dr. J. C. Merriam 

 (19a). 



The Trias of North America. 



Historical, Triassic fossils were discovered in Califor- 

 nia and Nevada by the State Geological Survey under 

 J. D. Whitney; these were thought by W. M. Gabb (9), 

 the paleontologist of the survey, to be nearly related to the 

 Upper Triassic fauna of the Alps, and certain species were 

 even looked upon as identical with European forms. This 

 was the first discovery of marine Trias in the western 

 hemisphere, and the third discovery outside of Europe, the 

 first being that in northern Siberia by Keyserling (14) ; the 

 second, that by R. Strachey (34) in the Himalayas of India, 

 and later described by Salter (30). Nothing more was 

 done with the Trias in America until the Survey of the 



(3) July I, 1904. 



