1890.] | Geology and Paleontology. 567 
cate that there is any difference in the age, so far as the indication 
from the shells is concerned. This bluff is right on the bank of the 
Yellowstone river, and the railroad cuts through it, which makes the 
cliff there conspicuous. Immediately below there is a short anticline, 
apparently a little island about a mile in extent, filled with character- 
istic Fox Hills Cretaceous fossils. I have been on the ground and 
collected large numbers of them, and everywhere we meet with them ; 
the wheels of the wagon as one drives over them crush the shells, so 
abundant are they; and there is do doubt that this is a typical Fox 
Hills bed, in Dr. White’s understanding of the term ‘ Fox Hills.” 
Now, as far as I can tell, and so far as he could tell from a careful 
study of the ground, this Iron bluff deposit—this Laramie or Fort 
Union leaf-bed—rests directly and immediately upon the Fox Hills 
bed. If there is any difference of age there is no indication at that 
point that it has been wanting from lack of comformity or from any 
other cause; and it is certainly a very natural conclusion that when 
one deposit rests comformably upon another at one point, and when 
at another point two formations, the lower one being the same as in 
the first case, have the same order and arrangement, the age of the 
overlying beds in both regions is the same. ‘That seems to be as clear 
a case of geological reasoning as we have. 
“I observe that our friends across the border, of whom we have re- 
presentatives here, are still using the term Laramie for this formation. It 
seems to me thatthe bulk of their Laramie is nothing more or less than our 
Fort Union, and they seem to be somewhat in doubt (at least so I learn 
from reading a paper which reached me only a day or two before L 
left Washington, with a Christmas greeting from Sir William Dawson) ; 
and I do not know but that we might as well settle the question in the 
way he has settled it in that paper asin any other way. He simply 
says that the time may yet come when, in fixing our arbitrary position 
for the line between the Cretaceous and the Tertiary, we may be 
obliged to draw it through that continuous deposit which we call the 
Laramie group. 
“ Dr, Newberry’s memory is entirely at fault when he says that in 
my ‘‘ Synopsis ’’ I called the Laramie and Fort Union group Tertiary. 
I have been criticised for arguing that they are Cretaceous, As a mat- 
mer of fact, I did not call themthe one or the other, or argue for either 
view. I first gave a perfectly unbiased review of opinion, in which the 
. advocates of each view were allowed to state their case in their own 
words. I then did what had never before been done. I presented the 
evidence from the fossil plants upon both sides in tabular form, getting 
