The Scottish Naturalist. 199 



ence must have endured for some considerable time. By-and- 

 by, however, the British Islands became united to themselves 

 and the continent, and the sea also retreated to a lower level 

 upon the coasts of Scandinavia and Spitzbergen. It was at this 

 stage that oaks grew at the higher elevations in the Scottish High- 

 lands.^ The climate, indeed, seems to have everywhere favoured 

 a most abundant development of arboreal vegetation. Even in 

 regions where trees will not now grow, such as many of the mari- 

 time districts of our country, the Outer Hebrides, Orkney, Shet- 

 land, Northern Norway, and the Faeroe Islands, we find plentiful 

 roots, trunks, and branches under the peat. In a recent number 

 of this magazine ^ I have described the discovery of an ancient 

 canoe in connection with the " buried forest " of the Tay valley, 

 from which, as well as other evidence, it may reasonably be in- 

 ferred that our area was occupied by Neolithic man before the 

 final insulation of the land took place. I cannot doubt, indeed, 

 that much of the buried timber in the deeper bogs and peat- 

 mosses of our islands, with the associated shell-marls and their 

 abundant remains of Irish deer, red deer, urus, and other cervine 

 and bovine animals, belong to Neolithic times and the last con- 

 tinental condition of our islands. 



What was the precise character of the climate during this post- 

 glacial period ? I think we may fairly conclude that the winter 

 season must have been much milder than it is now in north- 

 western Europe, while the temperature of summer, owing to the 

 greater extent of land, may have been somewhat warmer. From 

 the fact that a woody vegetation covered the Faeroe Islands, we 

 may likewise infer an absence of violent winds ; for, as a writer 

 in a recent number of the ' Quarterly Review ' has remarked, it 

 is to the long-continued cold winds and gales that the absence 

 or scarcity of trees in the higher latitudes is probably due. 



If now we turn to the deposits which in Scotland overlie the 

 '' forest-bed " and " submarine peat," we meet with strong evi- 

 dence to show that the " age of forests" was succeeded by a 

 period of colder conditions, when the climate was considerably 

 severer than the present. In the valleys of the Earn and the 

 Tay the " forest-bed " is overlaid by thick accumulations of finely- 

 laminated clays which, although usually stoneless, do yet contain 



1 It was probably at this period also that the flora of southern England 

 received its Iberian element, since it is difficult to believe that the plants in 

 question could have outlived the rigorous climate of the last glacial epoch. 



2 'Scottish Naturalist,' vol. v., p, i. 



