C. A. White—Floral Types in the Laramie Group. 121 
lected many invertebrate fossils which were afterward described 
remains, among which were those of Dinosaurs. Mr. Clarence 
King, accepting the conclusions of Dr. Newberry as to the 
Miocene Tertiary age of the plants here referred to, and those 
of Professor Cope as to the Cretaceous age of the Dinosaurs, 
expressed the opinion that the strata from which the former 
were obtained were distinct from those of the latter and of 
much later geological age. The following paragraph is quoted 
from his volume I, of the U. S. Geological Survey of the 40th. 
Parallel, p. 353: ‘‘The relations of conformity or nonconformity 
etween the plant-bearing beds of Fort Union, and the Dinosau- — 
rian beds are not given, and there is reason to believe that the 
plant beds represent a horizon of the great White River Mio- 
cene series which underlies the Pliocene over so large a part of 
the Great plains. * * * * I apprehend that the plant-horizon 
at Fort Union will be found to be nothing but the northward 
extension of the White River Miocene.” My reason for refer- 
Ting especially to this statement of Mr. King is that it occupies 
a place in the leading volume of one of the larger series of 
. 5S. Government geological publications, and it is therefore 
(although he distinctly states that he has never visited the 
region in question), liable to mislead those who have not per- 
Sonally studied the geology of that region, if it should pass 
unchallenged. 
During the summer of 1882 I gave especial study to the 
geology of the region about Fort Union, extending up the Yel- 
lowstone Valley, and including all the localities from which 
Dr. Hayden obtained the fossil plants here referred to. The 
result of that study has been to ascertain that only one forma- 
tion, namely, the characteristic Fort Union Group, which is 
nothing more or less than a part of the great Laramie Group, 
Oecupies that whole region. That is, with the exception of one 
or two small exposures of the Fox Hills Cretaceous Group, 
Upon which the Laramie strata rest conformably, no other than — 
x 
t num 
and Missouri, including many of Dr. Hayden’s localities, I 
collected fossil plants, shells and vertebrate remains. the 
mollusean shells are those which belong to characteristic 
* In the last May number of this Journal I gave an account of a small deposit 
which I found on the top of a butte about 100 miles south of Fort Union, w 
may be of later age than the Laramie Group; but in that deposit only a few fos- : 
sil fishes were found, and it is several hundre d feet above the fossil plant horizon. 
