CLIMATES OF GEOLOGIC TIME—SCHUCHERT. 303 
Although there were these great crustal movements toward the 
close of the Upper Cretacic, nevertheless they seem to have had no 
marked effect on the climates of the world, for nowhere has anyone 
shown the presence of unmistakable glacial tills of this age.t| Then, 
too, the floras of early Tertiary times are said to be of about the same 
character as those of the late Cretacic, and they indicate that the 
climates were warm with slight latitudimal variation, so slight that 
even in Greenland and Spitzbergen the early Tertiary floras were 
those of a moist and mild .climate. : 
Tertiary.—We have seen that there was no marked climatic change 
in the time from the Cretacic to the Eocene, but that there was a 
reduction in temperature is admitted by paleobotanists and students 
of marine life. Berry states that the Middle Eocene floras of Europe 
‘show many tropical characters absent in the earlier Eocene” (1910). 
The Oligocene marie faunas were prolific in species, and the largest 
of all foraminifers, the nummulites, although still present at this 
time, had their widest distribution and largest species in the Middle 
Kocene and especially in the Tethyian Sea of the Old World, extending 
from 20° South to 20° North latitude. (Stromer, 1909.) 
In Miocene time on Spitzbergen (Cape Staratschin) lived the 
swamp cypress (Tazxodium distichum miocenum), a leafy sequoia, 
pines and firs, besides various hardwood trees, such as poplars, 
birches, beeches, oaks, elms, magnolias, limes, and maples. The 
swamp cypress, Nathorst says, ‘formed forests, as in the swamps 
in the southern portion of the United States. This conclusion is 
also confirmed by the occurrence of the remains of rather numerous 
insects” (1912). All of the plants mentioned then flourished as 
far north as 79° North latitude, and even at nearly 82° in Grinnell 
Land. This is evidence that in early Miocene time the climate was at 
least warm-temperate in arctic America. 
Again, Dall (1895) states that in Middle Miocene time considerable 
reduction of the climate appeared, for the Atlantic Chesapeake faunas 
were those of temperate waters and they spread southward as far 
as the eastern area of the Gulf of Mexico. Similar conditions are 
noted by the same conchologist in the northern Pacific Ocean. 
The Tertiary was an era of extraordinary crustal movements, 
finally resulting in the greatest mountain chains of all geologic time. 
These movements began in early Eocene time in the Rocky Mountains 
and at the close of this epoch further deformation took place in the 
Klamath and Coast Ranges of Oregon and the Santa Cruz Mountains 
of California. In Europe the elevations of Tertiary time started 
1 At the Princeton meeting of the Geological Society of America, Dec. 29, 1913, Prof. W. W. Atwood 
announced the discovery of a tillite about 90 feet thick in the San Juan Mountains of southwestern Colorado. 
The age of these glacial deposits is somewhere between late Cretacic and late Eocene. We therefore are now 
on the road to finding the physical evidence of a reduced climate during or following the close of the Lara- 
mide revolution. 
