102 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



fessor Trail, in his ''Topographical Botany of Scotland," published 

 in the Annals of Scottish Xaturcd History, it does not grow in 

 the Orkney and Shetland Islands, Caithness, Ayr, and Selkirk. 

 In the Hebrides it was introduced by man. In a note on 

 Quercus Robur, Professor Trail states that the fact that this is 

 native in the Highlands is shown alike by the remains in peat- 

 bogs, and by the frequency of the Gaelic name in the names of 

 places, and that probably it has been introduced into every other 

 district in which it was not already native {Annals of Scottish 

 Natural History, No. 31, p. 166). But the investigation of 

 peat-bogs and the other deposits shows that the oak was one of 

 the prevailing native trees of the ancient forests, and flourished 

 all oA-er Scotland. With regard to the alder, this tree has been 

 supposed to have been introduced by man into the Hebrides, but 

 here again it must be considered native, as it has been found 

 in the peat-bogs of Lewis. Finally, the ash is stated by 

 Sower by, in his English Botany (p. 56), " to be perhaps not in- 

 digenous in the Highlands and extreme north of Scotland " ; 

 in Bentham and Hooker's Flora, it is said to be common in 

 Britain and truly wild, excepting in the northern parts of Scot- 

 land : while Professor Trail, in his "Topographical Botany," states 

 that its nativity is scarcely to be determined. But from the 

 evidence I have collected, it might be said with some certainty 

 that the ash is indigenous not only in southern Scotland, but 

 also in the north. The record of it in the Bay of Keiss, which 

 has already been mentioned, may be considered as trustworthy, 

 and its occurrence in the peat-bogs of Ayrshire and Roxburgh- 

 shire must also be accepted. Hugh Miller has also reported 

 finding the ash in the brick-clays of Portobello, which, however, 

 belong to the glacial period. Confirmation as to its existence 

 as a wild tree in the south is derived, further, from the fact 

 that many of the implements found in the crannogs are made of 

 ash wood. 



In closing, it should be noticed that while we have been only 

 endeavouring to illustrate, as far as possible, the distribution of 

 the forest trees found in the various post-glacial deposits, there 

 is no doubt that if a more minute examination was made of 

 many of them, shrubs, flowering, and probably some flower ess, 

 plants, would be discovered. This would, as in the case of the 

 trees, indicate which of the existing plants are native, and where 

 they grew in the past. 



