THE FLORA OF JAPAN. ub} 
On our northwestern coast, in the miocene of Vancouver’s 
Island, among a singular mixture of species referable to Sa- 
lix, Populus, Quercus, Planera, Diospyros, Salisburia, Ficus, 
Cinnamomum, Personia, or other Proteacee, and a Palm 
(the latter genera decisively indicating a tropical or sub- 
tropical climate), Mr. Lesquereux has identified one existing 
species, a tree characteristic of the same region ten or fifteen 
degrees farther south, namely, the Redwood or Sequoia sem- 
pervirens. In beds at Somerville referred to the lower or 
middle pliocene by Mr. Lesquereux, this botanist has recently 
identified the leaves of Persea Carolinensis, Prunus Caroli- 
niana, and Quercus myrtifolia, now inhabiting the warm sea- 
coast and islands of the southern States.? 
The pliocene quadrupeds of Nebraska also show that the 
climate east of the Rocky Mountains at this epoch was much 
warmer than now. About the upper Missouri and Platte 
there were then several species of Camel (Procamelus) and 
allied Ruminantia and a Rhinoceros, besides a Mastodon, 
an Elephant, some Horses and their allies, not to mention a 
corresponding number of carnivorous animals. These herbi- 
vora probably fed in a good degree upon herbage and grasses 
of still existing species. For herbs and grasses are generally 
capable of enduring much greater climatic changes, and are 
therefore likely to be even more ancient, than trees. These 
animals must have had at least a warm-temperate climate to 
live in: so that in latitude 40°- 48° they could not have been 
anywhere near the northern limit of the temperate flora of 
those days ; indeed the temperate flora, which now in western 
Europe touches the Arctic Circle, must then have reached 
equally high latitudes in central or western North America. 
In other words, the temperate floras of America and Asia 
must then have been conterminous (with small oceanic sepa- 
ration), and therefore have commingled, as conterminous 
floras of similar climate everywhere do. 
At length, as the post-tertiary opened, the glacier epoch 
1 These and other data, obligingly communicated by Mr. Lesquereux, 
have been published in the May number of the “ American Journal of 
Science and Arts,” 3 ser., xvii. 
