ORIGIN AND DEFINITION OF.THE TERM “LARAMIE” 5309 
but which is more abundant in the upper Montana,’ certain Cre- 
taceous coal-bearing sandstones which are now known to be Mesa 
Verde. With this exception, Lesquereux studied only beds of Upper 
Laramie age, making large collections from the immediate vicinity 
of the mines. He studied and recognized the sea-beach character 
of the conglomeratic sandstones just west of Carbon, which are now 
recognized as the base of the Upper Laramie. This conglomeratic 
sandstone contains pebbles now known to have been derived from 
the underlying Cretaceous and older rocks, and indicates an immense 
unconformity. His report, in the light of present knowledge, is 
extremely suggestive. Thus he refers the beds at Carbon to the 
“upper Lignitic” and suggests the equivalence of the conglomeratic 
sandstone just mentioned with “that of the upper member of the 
Lignitic of Colorado” (possibly meaning beds since reported as the 
Arapahoe). : 
Two reports by Hayden, clearly written before the final adoption 
of the word “‘ Laramie,” complete the history of the development of 
his knowledge and belief in this critical period. In a “Brief History 
of the Lignitic Group”* Hayden states that “the Lignitic group of 
the Northwest [is] believed to be continuous southward with the Colo- 
rado and Laramie beds.” In this report Hayden finally acknowl- 
edges the presence of coal in beds of true Cretaceous age, saying: 
One fruitful source of difference of opinion has been in the misunderstanding 
in regard to the different horizons of the coal strata of the West. That there are 
important coal-beds in rocks of well-defined Cretaceous age cannot be disputed, 
and I have long since yielded that point. What we wish to show more clearly is 
that there exists in the West a distinct series of strata which we have called the 
Lignitic group, and that it is entirely separate paleontologically and geologically 
from a great group of strata in the lower Cretaceous,3 and perhaps extending down 
into the Jurassic, which contain a great number of thick and valuable beds of 
coal. It is not necessary to discuss the question whether the term Lignitic should 
be applied to either or both groups. I have used the term Lignitic for the upper 
« Hayden recognized this in 1875 (Bulletin, U. S. Geological and Geographical 
Survey of the Territories, Vol. I [1876], p. 404), and it has since been abundantly proven. 
2 Kighth Annual Report, U.S: Geological Survey of the Territories for 1874, 1876, 
Pp- 19-27. 
3 The phrase ‘“‘lower Cretaceous” is not here’used in the present technical sense 
(Lower Cretaceous or Comanche beds were unknown to Hayden) but rather in the 
sense of underlying. 
