Geol.-Vol. I.] SMITH— COMPARATIVE STRATIGRAPHY. 349 



D in locality No. i, and this part of the section unquestion- 

 ably belongs to the Lower Trias, although it is not likely 

 that the entire thickness of beds there is referable to this 

 division. In a later paper Dr. C. A. White (41) expressed 

 the opinion that the Meekoceras fauna of Idaho ought pos- 

 sibly to be placed in the Permian rather than in the Trias, 

 because of the conformity with the Carboniferous beds 

 below, and because of the presence in the fauna of certain 

 Carboniferous elements. These were precisely the argu- 

 ments used ten years later by F. NoetHng for placing the 

 Lower Triassic faunas of India in the Permian, but there is 

 just as little ground for this in the one region as in the other. 

 This question has been fully discussed by the writer (33^) 

 in a recent paper. 



In 1888 Professor Alpheus Hyatt discovered a third 

 locality for Lower Triassic ammonites in southeastern Idaho, 

 in the Aspen Mountains, in Wood Canon, about nine miles 

 east of Soda Springs. In 1900 and 1903 the writer visited 

 this same locality, which lies only a few miles southwest of 

 locality No. 2 of White, The joint collections of Professor 

 Hyatt and the writer yielded the following ammonites:^ 

 Danubites whiteanus Waagen, Damibites sp. nov., Meeko- 

 ceras gracilitatis White, Meekoceras three new species (of 

 which one maybe identical with M. boreale Diener), M. 

 (Koninckites) mtishbaclianiim White, M. (Gyronites) aflan- 

 atuni White, and two other species of the same subgenus, 

 Asptdttes sp. nov., Flemmgites sp. nov., Ofhiceras sp. 

 nov., Hedenstrmnia sp. nov., Clyfites sp. nov., Ussuria 

 two new species, and Nannites sp. nov. Besides those here 

 listed there were found several new genera of the same 

 families. 



This fauna is intimately related to the Lower Triassic 

 faunas of India and eastern Siberia, with several species that 

 may even be identical with those from Asia. It contains 

 several genera hitherto known only from the Lower Trias 

 of India, and others previously found only in the Profty- 



1 The new genera and species of this fauna will be described in the publications of the 

 United States Geological Survey. 



