298 REPORT OF THE AMERICAN COMMITTEE. 
NOTE ON THE CENOZOIC SERIES. 
The Geology of the Uinta Mountains, by Major J. W. Powell", 
appeared, according to the date on the title page, in 1876, one and 
two years prior to the vols. II. and I., respectively, of the Re- 
ports of the Surveys of the Fortieth Parallel, by Captain Clar- 
ence King. It is necessary, therefore, to ascertain whether any 
of the names proposed in the former work antedate those of 
the latter. The Cenozoic series for the region in question, ad- 
mitted by Powell, are the following, in descending order: 
Bishops' Mountain Conglomerate, 300 feet. 
Brown's Park, 1800 feet. 
Bridger, 2000 feet. 
Upper Green River, 500 feet. 
Lower Green River, 800 feet. 
Bitter Creek, 3000 feet. 
The Bridger of this section is the Bridger of Hayden, or the 
Middle Eocene, and the Green River beds are also those so-called 
by Hayden, Above this series the Brown's Park division is in 
the place of the Uinta of? King, for which I have used in the 
preceding pages the name Diplacodon beds of Marsh. No 
vertebrate fossils are reported from this formation by Powell, so 
that it is not possible to be sure whether the formation is the 
same as that described by King or not. The typical locality of 
the latter is not mentioned by Powell. Should it prove to be the 
same as the Uinta formation of King, the name Brown's Park 
series must be retained, as having priority of })ublication. 
The Bishops' Mountain Conglomerate is a late forma- 
tion which covers the Eocene beds of Southwestern Wyoming 
unconformably. Its exact age has not been yet ascertained, as it 
contains no fossils. Powell remarks that it has the appearance 
of a glacial drift, but he prefers not to consider it as due to such 
a cause without further evidence. It is described by Endlich, in 
Hayden's Annual Reports, as the Wyoming Conglomerate. I do 
not know which name is prior. 
