192 B. N. A. BOUNDARY COMMISSION. 
confirmed in his opinions previously expressed. Ile believes the Eocene 
of America and Europe to be identical in general characters, and as a 
resumé of his conclusions writes :—“ I am, I think, authorized to deduce 
the following conclusions: That the great Lignitic group must be con- 
sidered as a whole and well characterized formation, limited at the base 
by the fucoidal sandstone, at its top by the conglomerate beds ; that inde- 
pendent from the Cretaceous under it and from the Miocene above it, our 
Lignitic formations represent the American Eocene.” * In 1874, Prof. 
Lesquereux appears in some degree to modify this statement, by placing 
the beds at Carbon in the middle Miocene, and including those of Evans- 
ton and a few other localities, in the Upper Eocene, while classing the 
great majority of lignite-bearing rocks—including those of Colorado and 
Wyoming, with those also of Coalville in Utah, Nanaimo in Vancouver 
Island, and the Placiére coal of New Mexico—as Lower Eocene. + He 
believes that the age of the flora of many of the European beds referred 
td the Miocene, has not been fixed with sufficient precision to admit of 
their being used as terms of comparison. 
444, Prof. Newberry draws attention to the fact of the diversity of 
Prof. Lesquereux’s so-called American Eocene plants from those of the 
recognized Eocene of Europe, and does not think his reference of the 
lignite beds to the Eocene justified, writing :—‘“‘ This conclusion I am 
unable to accept, from the fact that the general facies of the Missouri lig- 
nite flora, is altogether unlike that of the European Eocene, and it is 
identified with the Miocene flora of Arctic America, Iceland, the He- 
brides, and Central Europe, by most of its genera, and by a considerable 
number of well-marked species.” ¢ 
+445. Prof. Cope appears first to have referred beds of this forma- 
tion to the Cretaceous, on account of their reptilian fauna in 1869.§ He 
has described the remains of the Dinosaurian reptile from the Bitter 
Creek series near Black Butte, where they occur in the closest relation 
with a coal bed, and were surrounded by a mass of vegetable debris, and 
associated with Viviparus trochiformis, already mentioned. He insists on 
the importance of this discovery, and writes :—“It is thus conclusively 
proven that the coal strata ot the Bitter Creek Basin of Wyoming Ter- 
ritory, which embraces the greatest area yet discovered, were deposited 
during the Cretaceous period, and not during the Tertiary, though not 
very long preceding the latter.” || 

*U. 8 Geol. Surv. Territ., 1872, p. 350. 
t Am. Journ, Sci. and Arts, June. 1874. U. 8. Geol, Surv. Territ., 1873. 
} Am, Journ. Sci. and Arts, April. 1874. § See U. S. Geol. Surv. Territ., 1873, p. 434. 
|| On the existence of Dinosauria in the Transition beds of Wyoming. 


