376 OLDER MESOZOIC FLORAS OF UNITED STATES. 
Todd Gulch, and on the 15th Mr. Storrs and I found them not only 
in the original Todd locality, but lower in the same gulch at two hori- 
zons, one 20 feet and the other 30 feet lower in the beds. 
Professor Diller and Mr. Brown devoted the greater part of the 
time to carefully working out the stratigraphy. They followed the 
plant-bearing slates all the way from Olalla Creek to the Todd Gulch 
and proved their complete continuity. On Olalla Creek these slates 
are immediately overlain by the Eocene, only a short distance below 
the uppermost plant bed. On Buck Mountain, on the contrary, they 
are overlain by a bed of conglomerate, doubtless of the same age, which 
underlies the Aucella-bearing Knoxville beds on which the Eocene here 
rests. Everywhere to the east isa very thick bed of conglomerate, 
through which is intruded a great thickness of eruptive rock, princi- 
pally serpentine. Still farther east, on the Nickel Mountain, are other 
Aucella beds, as if occupying the eastern slope of a great Mesozoic 
anticline, and when the bed of Cow Creek is reached at Riddles the 
higher Horsetown beds appear in force. 
Such seems to be a general view of the much-discussed stratigraphy 
of the Buck Mountain region, and thus far the fossil plants furnish 
the only evidence of the existence of a great Jurassic deposit running 
through the State of Oregon; but this evidence is not only conclusive 
from a paleontological point of view, but when correlated with all the 
remaining facts and worked out, as was done by our party, it proves 
to be perfectly harmonious and consistent. 
There remained the problem presented by Mr. Brown’s collection 
from near Nichols station, on Cow Creek, 14 miles above and nearly 
southwest from Riddles. A glance at the map shows that Nichols 
station is exactly due south of Buck Peak, and all the plant localities 
in the Buck Mountain region are arranged along a nearly north-south 
line. The strike of the slates, as was shown, varies considerably even 
in short distances, but probably averages nearly north and south. 
The distance in a straight line from the Olalla bed to the Nichols bed 
is nearly 7 miles due south. We were unable to follow the strike with 
our pack train, but were obliged to go down one of the tributaries of 
Doe Creek from the eastern slope of Buck Mountain and then to fol- 
low Doe Creek to its junction with Cow Creek, 3 miles below Nichols 
station, thus avoiding the great Table Mountain on the west. 
Very little additional to Mr. Brown’s collection was found in the rail- 
road cutting, but it was seen that we had here the same slates as those 
of the Buck Mountain district and that they came in in a regular way 
from the north. At this point Cow Creek has a course slightly west 
of north and the slates cross its channel very obliquely and even fol- 
low the bed of the stream for some distance. At the point where they 
‘emerge on the right bank to the north they expose their upturned 
edges for a long distance over that portion of the stream bed which is 
