SEQUOIA AND ITS HISTORY. 593 
before the glaciation of the region. Among the fossil specimens 
already found in California, but which our trustworthy palæ- 
ontological botanist has not yet had time to examine, we may 
expect to find evidence of the early arrival of these two redwoods 
upon the ground which they now, after much vicissitude, scantily 
occupy. 
Differences of climate, or circumstances of migration, or both, 
must have determined the survival of Sequoia upon the Pacific, 
and of Taxodium upon the Atlantic coast. And still the redwoods 
will not stand in the east, nor could our Taxodium find a congenial 
station in California. 
‘ to the remaining near relative of Sequoia, the Chinese Glyp- 
tostrobus, a species of it, and its veritable representative, was 
contemporaneous with Sequoia and Taxodium, not only in tem- 
perate Europe, but throughout the Arctic regions from Greenland 
toAlaska. Very similar would seem to have been the fate of a 
more familiar gymnospermous tree, the Gingko or Salisburia. It 
is now indigenous to Japan only. Its ancestor, as we may fairly 
call it, since, according to Heer, ‘it corresponds so entirely with 
the living species that it can scarcely be separated from it,” once 
inhabited Northern Europe, and the whole Arctic region round to 
Alaska, and had even a representative farther south, in our 
Rocky Mountain district. For some reason, this and Glyptos- 
trobus survived only on the shores of Eastern Asia. 
Libocedrus, on the other hand, appears to have cast in its lot 
with the Sequoias. Two species, according to Heer, were with 
them in Spitzbergen. Of the two now living, L. decurrens, the 
incense-cedar, is one of the noblest associates of the present red- 
Woods ; the other is far south in the Andes of Chili. 
The genealogy of the Torreyas is more obscure; yet it is not 
unlikely that the yew-like trees, named Taxites, which flourished 
with the Sequoias in the tertiary Arctic forests, are the remote 
ancestors of the three species of Torreya, now severally in Florida, 
ìn California, and in Japan. 
As to the pines and firs, these were more numerously associated 
with the ancient Sequoias of the polar forests than with their 
present representatives, but in different species, apparently more 
like those of Eastern than of Western North America. They 
must have encircled the polar zone then, as they encircle the 
Present temperate zone now. 
AMER. NATURALIST, VOL. VI. 38 
