414 FLORA OF Tin: LARAMIE tiUOFP. 



inj; to tlie Tertiary formation, the only point of special interest brought 

 I'oitli is liis iittciiii)t to subdivide tlie American Tertiary into suhonli 

 nate groups based- upon the analogies afl'orded by their floras with 

 those of established horizons in Europe and elsewhere. Thus to the 

 Eocene, lie refers Eaton Pass and Purgatory Canon, in New ]\Iexico; 

 Marshall's Mine, in Colorado; Washakie Station and Evanstou, in Wyo- 

 ming; and Siiring Caiioiy, near Fort Ellis, in Montana, as well as Yellow- 

 stone Lake, which also belongs to the upper district. To the Lower 

 Miocene he refers Carbon Station, Junction Station, Medicine Bow, 

 Rock Creek, and the Washakie group, in Wyoming; and the Fort Union 

 group, in Montana and Dakota. To tlie Middle Miocene are referred 

 Barrel Sinings and Muddy Creek, in Wyoming; Henry's Fork of Snake 

 Eixer; and Elko Station, Nevada. Among the localities the geological 

 liosition of which is marked as unknown are the important, and now 

 well known ones. Point of Eocks and Green River. In a table of dis- 

 tribution the data are assumed to exist to justify this classification. 



Notwithstanding these efforts to sustain the argument for the Ter- 

 tiary age of the central coal formation of the West, it had been so weak- 

 ened by the blows of King and Marsh, coupled with tLe admissions of 

 • Meek, that little re maim d but the evidence afl'orded by the fossil plants 

 in its support, and this, though abundant in quantity, was naturally dis- 

 trusted, and had been enfeebled by the considerations urged against it 

 by Le Coute. Meek himself did not hesitate to refer forms of Ostrea 

 and Anomia, from Point of Eocks on the Union Pacific Eailroad and iu 

 the typical Bitter Creek district, to the Cretaceous,' and now there was 

 destined to come forward a new discovery of great importance, the full 

 weight of which fell upon that side of the question. In the summer of 

 1872 Messrs. Meek and Bannister discovered the bones of a large saurian 

 near Black Buttes Station in the Bitter Creek series, and Professor Cope 

 soon after visited the spot and studied the fossils. He laid his results 

 before the American Association for the Advancement of Science at 

 Dubuque in August of that year, and published his descriptions in the 

 Proceedings of the American Pliilosojihical Society for September 19. 

 In this pajier he remarks (p. 483) : " From the above descriiition it is evi- 

 dent that the animal of Black Buttes is a Dinosauriau reptile. * * * 

 It is thus conclusively proven that the coal strata of the Bitter Creek 

 Basin of Wyoming Territory, which embraces the greater area yet dis- 

 covered, were deposited during the Cretaceous period, and not during 

 the Tertiary, though not long i»receding the latter." And, commenting 

 upon the same subject in the American Naturalist for November, 1S71', he 

 says: "Thisdiscovery places this group without doubt within the limits 

 of the Cretaceous period." 



Mr. Lesquereux was also in the field this j-ear (1872), and his inves- 

 tigations, at the request of Dr. Hayden, were specially directed to " posi- 



' Fifth Aiitm.-il Report United States Geological Survey of the Territories, 1871, p. 

 375. 



