224 ESSAYS. 
lock Spruce, Arbor-Vite, Taxodium, or Torreya. As com- 
pared with northeastern Asia, Europe wants most of these 
same types, also the Ailanthus, Gingko, and a goodly number 
of coniferous genera. I cannot point to any types tending 
to make up the deficiency, that is, to any not either in east 
North America or in northeast Asia, or in both. Cedrus, 
the true Cedar, which comes near to it, is only north African 
and Asian. I need not say that Europe has no Sequoia, and 
shares no special type with California. 
Now the capital fact is, that many and perhaps almost all 
of these genera of trees were well represented in Europe 
throughout the later Tertiary times. It had not only the 
same generic types, but in some cases even the same species, 
or what must pass as such, in the lack of recognizable distince- 
tions between fossil remains and living analogues. Probably 
the European Miocene forest was about as rich and various as 
is ours of the present day, and very like it. The Glacial pe- 
riod came and passed, and these types have not survived there, 
nor returned. Hence the comparative poverty of the existing 
European sylva, or, at least, the probable explanation of the 
absence of those kinds of trees which make the characteristic 
difference. 
Why did these trees perish out of Europe but survive in 
America and Asia? Before we inquire how Europe lost them, 
it may be well to ask, how it got them. How came these 
American trees to be in Europe? And among the rest, how 
came Europe to have Sequoias, now represented only by our 
two Big Trees of California? It actually possessed two species 
and more ; one so closely answering to the Redwood of the coast 
ranges, and another so very like the Sequoia gigantea of the 
Sierra Nevada, that, if such fossil twigs with leaves and cones 
had been exhumed in California instead of in Europe, it would 
confidently be affirmed that we had resurrected the veritable 
ancestors of our two giant trees. Indeed, so it may probably 
be. ‘“Coelum non animam mutant,” ete., may be applicable 
even to such wide wanderings and such vast intervals of time. 
If the specific essence has not changed, and even if it has suf- 
fered some change, genealogical connection is to be inferred 
in all such cases. 
