ORIGIN AND DEFINITION OF THE TERM “LARAMIE” 529 
and the Tertiary. They conformably overlie the Fox Hill of Meek and Hayden, 
and are developed throughout a large part of Wyoming, as well as upon the great 
plains east of the Rocky Mountains south of the forty-first parallel. That there 
might be no misunderstanding as to the stratigraphical position and nature of 
the rocks themselves, Dr. Hayden and I mutually agreed to know them hereafter 
as the Laramie group, and to leave their age for the present as debatable ground, 
each referring them to the horizon which the evidence seemed to~him to 
warrant... ... 
The great sandstone series of the Fox Hill is conformably overlain by a con- 
tinuation of the sandstones, which attain a thickness of from 1,500 to 5,000 feet, 
varied very greatly in-lithological character over different areas, but in general 
characterized by the frequent occurrence of workable beds of lignite and innumer- 
able seams of carbonaceous clay. The fossil forms which are found in this series 
have led to a disagreement, which has now become historic, as to the age of the 
beds. They were at first, by Meek and Hayden, held to be distinctly Tertiary. 
That opinion has since been so modified as to lead those gentlemen to designate 
them as beds of transition. On the other hand, Dr. Le Conte, Professor Newberry, 
Professor Stevenson, and Major Powell have all committed themselves to the 
view advanced by me in Volume III of this series in 1870, that the whole of the 
conformable series is Cretaceous. During the slow gathering of the evidence 
which shall finally turn the scale, I proposed to Dr. Hayden that we adopt a 
common name for the group, and that each should refer it to whatever age his 
data directed. Accordingly, as mentioned in the opening of this chapter, it was 
amicably agreed between us that this series should receive the group name of 
Laramie, and that it should be held to include that series of beds which conform- 
ably overlies the Fox Hill.?.... 
Here, with those who follow Hayden, the Cretaceous series comes to an end. 
Conformably over this lies the group which Hayden and I have agreed to call 
the Laramie, which is his Lignitic group, and is considered by him as a transition 
member between Cretaceous and Tertiary. There is no difference between us 
as to the conformity of the Laramie group with the underlying Fox Hill. It is 
simply a question of determination of age upon which we differ.3 
It is evident from the above: (1) that Laramie was adopted as a 
name for the beds which Hayden called Lignitic in Wyoming and 
Colorado,4 and (2) that the beds so included were believed by both 
Hayden and King conformably to overlie the Fox Hills sandstone. 
Considered with other available data, it is unquestionably true that 
t Report of the Geological Exploration of the Fortieth Parallel, Vol. I (1878), 
p- 208. 
2 [bid., Pp. 331- 3 [bid., p. 348. 
4 This is further shown by the following phrases on p. 333 of King’s report: ‘‘The 
Laramie or Lignitic period,” ‘“‘Hayden’s Lignitic (now the Laramie) series.” 
