Alg.), Alnus rotundifolia., Salix pedicellata, Prunus avium, &c.; and thus they have some elements in common with the deciduous forests of central Europe.
There were oaks, beeches (scarcely distinguishable from existing species), birches, planes and willows (one closely related to the living Salix candida), laurels, represented by Sassafras and Cinnamomum, magnolias and tulip trees (Liriodendron), myrtles, Liquidambar, Diospyros and ivy.
This was not confined to the north but may occur on the mountains of England and Wales: Salix herbacea, Silene acaulis and Dryas octopetala will serve as examples.
And Reid has shown that during the glacial period the existing flora was replaced by an arctic one represented by such plants as Salix polaris, S.
At the close of the glacial period the alpine floras retreated to the mountains accompanied by an arctic contingent, though doubtless many species of the latter, such as Salix polaris, failed to establish themselves.