428 THE ICE AGE IN NORTH AMERICA. 



here remarkably in some parts of the Atlantic coast, especially 

 the cooler temperate ones. The poverty of the European sylva 

 is attributable to the absence of our Atlantic American types, 

 to its having no magnolia, liriodendron, asimina, negundo, no 

 iEschulus, none of that rich assemblage of leguminous trees 

 represented by locusts, honey-locusts, gymnocladus, and cla- 

 drastis (even its cercis, which is hardly European, is like the 

 Oalifornian one mainly a shrub) ; no JVyssa, nor Liquidambar; 

 no Ericaceae rising to a tree ; no bumelia, catalpa, sassafras, 

 Osage orange, hickory, or walnut ; and, as to conifers, no hem- 

 lock, spruce, arbor- vitae, taxodium, nor Torreya. As compared 

 with northeastern Asia, Europe wants most of these same 

 types, also the ailantus, gingko, and a goodly number of conif- 

 erous genera. I can not 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 spe- 

 cial 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 distinctions be- 

 tween fossil remains and living analogues. Probably the Eu- 

 ropean Miocene forest was about as rich and various as is ours 

 of the present day, and very like it. The Glacial period came 

 and passed, and these types have not survived there, nor re- 

 turned. Hence the comparative poverty of the existing Eu- 

 ropean sylva, or at least the probable explanation of the ab- 

 sence 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 



