520 JAMES PERRIN SMITH 



Paleozoic, for if Otoceras, Medlicottia, Xenodiscus, and Xenaspis can 

 range into the Mesozoic, there is no known reason why Productiis 

 should not have done so. Indeed, Xenaspis and Xenodiscus 

 range up into the Middle Trias, associated with faunas charac- 

 teristic of the Muschelkalk. 



C. Diener ^ meets Noetling's argument by stating that if 

 the Ceratite formation of India is not of Lower Triassic age, 

 then we have nowhere in the world a strictly marine equivalent 

 of the Werfen beds, and that we have the anomaly of Middle 

 Triassic beds lying conformably on Permian. He shows that 

 the marine Permian of the Alps, which lies below the Werfen 

 beds, has not the fauna of the Otoceras beds, but one analogous 

 to that of the Productus limestone. Diener admits that the 

 Otoceras horizon is older than the fossilferous portion of the 

 Werfen beds, but thinks that the rule of priority of reference 

 must be followed, where there are no paleontologic grounds 

 against it and many for it. He also cites a recent paper by A. 

 Bittner "" to show that there is found in the Proptychites beds of 

 Ussuri a typical pelecypod and brachiopod fauna of Werfen 

 character ; it must be admitted, however, that this fauna was 

 not found with the ammonites, and might belong considerably 

 above them. 



The most direct comparison with the European Trias has 

 been made by Lukas Waagen,^ who shows that in the Ceratite 

 marls and the Ceratite sandstone of India he has identified a 

 number of pelecypods identical with forms characteristic of 

 middle and upper Werfen beds of the Alps. This leaves the 

 question about as A. von Kraft stated it. The Ceratite forma- 

 tion, from the Ceratite marls up, certainly belongs to the Lower 

 Trias, since the Werfen beds are the type, while the Otoceras 

 beds of the Himalayas, or their equivalent, the lower Ceratite 

 limestone, may belong to the upper Permian. But the fauna of 



' Centralblatt fiir Min. Geol. und Pal. Bd. I, 1900, p. i, " Ueber die Grenze des 

 Perm- und Triassystems, etc." 



* Mem. Com. Geol. St. Petersbourg, Vol. VII, 1899, " Verstein. aus den Trias-Abla- 

 gerungen des Siid-Ussuri Gebietes in der Ostsibirischen Kiistenprovinz. 



3 Centralblatt fiir Min. Geol. und Pal. Bd. I, 1900, p. 285. 



