JURA-TRIAS. 537 



souri and country north of Ft. Laramie and eastwardly to the Missouri River. 

 Hayden (Colorado and New Mexico, 1859,) speaks of the Triassic and Jurassic 

 at Las Vegas, but he only found a Mytalus. In Geological Report, 1874, he re- 

 fers Glen Eyrie and the Garden of the Gods to the Trias. He also speaks of a 

 narrow belt of Jurassic from the Union Pacific Railway southwardly into New 

 Mexico. 



In the same volume Peale describes certain beds of Triassic and Jurassic on 

 the Grand River west of the Rocky Mountains, also on Gunnison River near the 

 mouth of Smith's Fork and on Eagle River. The lower Grand Canon of the 

 Gunnison has been called Unaweep (meaning red earth) by the Indians. In the 

 same region Peale assigns nearly a 1000 feet overlying the so-called Trias to the 

 age of the Jura — but no fossils. 



In Hayden's Report, 1870, Meek gives a list of nine species of Jurassic fos- 

 sils from Henry's Fork of Green Ri\ er, Red Buttes, Salinas and Como. In 

 Hayden's Report, 1872, Cinnabar Mountain on the Yellowstone is made to in- 

 clude certain strata with Jurassic fossils. Jurassic is also stated to occur on Gal- 

 latin River and at the three forks of the Missouri Peale in the same volume 

 gives a section at the head of the Gallatin including Cretaceous, Jurassic, Triassic 

 and Carboniferous and names four fossils as being certainly Jurassic. In this 

 volume Prof Meek gives a catalogue of twenty two species of Jurassic from near 

 the canon of the Yellowstone; eleven species from Spring Creek, Montana; seven 

 from Ft. Hall, Idaho, and eight from Cinnabar Mountain. 



In Hayden's Report, 1873, Marvin gives sections of Jurassic near Bear's 

 Creek, Big Thompson, near St. Vrain's, etc., but mentions no fossils. 



Hayden's Report, 1875 : Peale describes the Jurassic and Triassic of Gunni- 

 son and Grand Rivers, and furnishes comparative sections from Powell, New- 

 berry, Gilbert and Howell. Howell's section includes four species of Jurassic 

 fossils from southern Utah with 2000 feet of Jurassic rocks. He also indicates 

 Trias at same place. Powell has over 5000 feet of Jurassic and Trias from 

 plateau of southern Utah, and Gilbert has iSoo feet of Trias from Ft. Wingate, 

 New Mexico. 



Hayden's Report, 1876 : White speaks of the overlying Jurassic as soft, 

 greenish, and reddish and purple sandstone beds with sandy calcareous shales. 

 He refers to fossils collected by Major Powell in southern Utah which he regards 

 as Triassic, and that the relative position of the shales justifies their reference to 

 the Trias but the invertebrate fossils point to a Jurassic age. He therefore calls 

 the beds Jura-Trias. Endlich, in the same volume, says that all along the Front 

 Range the Trias is prominent, disappearing toward the south. Peale also speaks 

 here of the Juras-Trias on Grand River. 



In Hayden's Report, 1877, Peale gives section of Jura-Trias in southeastern 

 Idaho and western Wyoming, 2500 feet of Jurassic and 3000 feet of Triassic. 

 The fossils are described by White in Bulletin of Survey, Vol. V, No. i, and in- 

 clude quite a list of fossils : Crinoidecs, Cephalopoda and Acephala, etc. Peale also, 

 in same Bulletin, enumerates over twenty species from Jura-Trias of southeastern 



