TRIASSIC. 529 



The "Meekoceras beds" of Peale are not recognized either by him or by Schultz 

 in western Wyoming, 25 miles east of John Grays Lake. Smith ^*'* gives the 

 following description of the occurrences in Idaho : 



Many years ago Dr. A. C. Peale discovered in southeastern Idaho and southwestern Wyo- 

 ming a series of fossiliferous beds lying below the red beds and above the Carboniferous lime- 

 stone. The fossils found in this formation were described by Dr. C. A. White and assigned to 

 the Lower Trias. Cephalopods were found at but two places — locality No. 1, in southeastern 

 Idaho, 65 miles north of Utah, 18 miles west of Wyoming, and 5 miles west of John Grays Lake; 

 locality No. 2, 15 miles east of south from locality No. 1. 



The section at locality No. 1, according to Dr. C. A. White, is as follows: 



Feet. 



A. (Uppermost beds.) Limestones and shales, with Terebraiula semisimplex White, T. angitsA 



tata Hall , Aviculopecten idahoensis Meek [l, 000 



B. Limestones, with Eumicrotis curta, and Aviculopecten idahoensis Meek J 



C. Greenish and reddish shales and sandstones, with Aviculopecten pealei '\\'hite 850 



D. Bluish-gray limestones, fossiliferous near the base, with Meekoceras gracilitatis White, ^M. 



miLshhachanum White, Arcestesf cirratus AATiite 700 



E. Reddish and greenish sandstones 400 



F. Dark-blue sandstone i 



G. Quartzite J 



H. Massive gray limestone 400 



At locality No. 2 were found Meekoceras gracilitatis White and M. aplanatum White, in 

 limestone similar to that marked D in locality No. 1, and this part of the section unquestionably 

 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 expressed the opinion that the 

 Meekoceras fauna of Idaho ought possibly 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 arguments used 10 years later 

 by F. Noetling 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 in a recent paper. 



In 1888 Prof. Alpheus Hyatt discovered a third locality for Lower Triassic ammonites in 

 southeastern Idaho, in the Aspen Mountains, in Wood Canyon, about 9 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 Prof. Hyatt and the writer 

 yielded the following ammonites:" Danubites whiteanus Waagen, Danubites sp. nov., Meeko- 

 ceras gracilitatis White, Meekoceras, three new species (of which one may be identical with 

 M. boreale Diener), M. (Koninckites) mushbachanum White, M. (Gyronites) aplanatum White, 

 and two other species of the same subgenus, Aspidites sp. nov., Flemingites sp. nov., Ophiceras 

 sp. nov., Hedenstroemia sp. nov., Clypites 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 Proptychites beds of Ussuri Bay in Siberia; it is therefore referred with certainty to the 

 Brahmanic stage of the Scythis series. It may be correlated with the Ceratite marls and the 

 lower part of the Ceratite sandstone of the Salt Eange of India. 



The following notes are contributed to this manuscript by C. L. Breger: 



The "Meekoceras beds" are in southeastern Idaho nearly 3,000 feet thick and include Lower 

 Triassic and apparently also Middle Triassic, while at the top, underlying the red beds, is a 

 zone which appears to be of Upper Triassic age, containing Myophoria cf. lineata Mstr. and 



"The new genera and some of the species of this fauna have been described in Prof. Paper U. S. Geol. Survey 

 No. 40, by Hyatt & Smith.— B. W. 

 48011°— 12 34 



