1890. ] Geology and Paleontology. 565 
in the lower Laramie—the original Laramie formation—there is a large 
predominance of such genera as Ficus, and also many palms, which, to 
the mind of a paleobotanist naturaily and probably correctly suggest a 
warmer climate. 
‘t Whatever may be true in regard to the difference of age—and it 
seems to me that the two must go together—I am quite satisfied that a 
warmer climate prevailed during the period of the deposition of the 
Wyoming and Colorado beds than that which prevailed during the 
deposition of the Fort Union beds. Among the leading genera of the 
upper beds are Populus and Platanus. Some of these forms are, I admit, 
very irregularand peculiar, but they are not found in any such abundance 
least, grow in the colder climates, and very few species of Ficus, very few 
in the lower beds. They are more northern forms—forms which now at 
genera of palms, are found, so far as my own collection is concerned, 
in the Fort Union beds. Moreover, as Dr. Newberry has stated, there 
are forms in the Fort Union which have an exceedingly recent facies, 
but I am very loath to argue from this a Tertiary age. For instance, 
there are what seem to be the leaves of the identical species of hazel 
which grows now in the eastern parts of the United States; yet I 
hesitate to argue from this that the formation is necessarily’ very 
recent. 
“ In fact, the material from the Fort Union formation which is still in 
my hands (partly for the reason that I was unable to identify it with 
the published flora of the globe, and partly because I was unable to 
publish more at that time) inclines me to believe that there would 
really be, as I then stated, no inconsistency in assigning to the Fort 
Union an age as ancient as the closing period of the Cretaceous 
system. Some of the facts I might enumerate here, but this would be 
perhaps tedious ; but some of the forms are certainly not to be identified 
with any of the genera that have been found in the fossil or the living 
state. Such forms cannot be regarded as having geological importance 
in fixing age, yet they go a long way in the direction of showing us 
that the age may be more ancient than has been supposed. The genus 
Trapa has been found in both groups, but I am not thoroughly satisfied 
that the species are identical. In my anxiety not to multiply species, 
I called it by the name given to the form described by Lesquereux 
from the Point of Rocks beds, though it may prove to be a distinct 
species; yet we may never know, from the fact that the material 
collected by him was inadequate. I have collected from the Fort 
Union beds specimens of that plant containing entire rosettes of leaves as 
they would lie on the surface of the water, and showing to my mind 
Am 
