54 MR FRANCIS J. LEWIS 



ancient birch forest in this position than to find the remains of the upper forest far 

 above modern tree limits at 3000 feet on the Grampian Mountains. 



During the examination of this region several sections were taken on the banks of 

 Sma Lochs, S.E. of Stourborough Hill — a series of lochs of very irregular outline 

 situated at 200 feet above sea-level. The water apparently occupies a hollow in the 

 peat, as far as can be seen from the banks. Sections were made along the north side of 

 the lochs. Here the banks are formed of peat which at the margin reaches a depth of 

 10 feet below water-level. 



The following succession of strata was observed : — 



Characteristic Plants. 



1. Eriophorum vaginatum. 



2. CaLluna vulgaris. 



3. Betula nana. 



4. Betula alba. 



5. Structureless peat with clay. 



6. Salix Arbuscula. 



Accompanying Plants. 



1. Sphagnum, Seirpus cxspitosus. 



2. Erica Teiralix. 

 3. 



4. 

 5. 

 6. Empetrum nigrum. 



Stone pavement. 



Whilst the general succession of vegetation is similar to that already described 

 it is remarkable to find the greater depth of peat below water-level. The 

 sequence and relation of the beds to the water-level in the loch is shown in 

 fig. 3. In the absence of a boat upon the loch it was impossible to take borings 

 to see how far the peat extends under the loch, but the horizontal strata of dwarf 

 willow, peaty clay, birch forest, and arctic birch which lie below water-level, and 

 stretch at least some distance under the loch, must once have been exposed. A case 

 like this shows a complete reversal of peat formation, and it is difficult to see how 

 such a comparatively large loch could be formed in this way. It might be pointed out 

 that the water-level was rather below than above the average height, as the loch was 

 examined at the beginning of September after a dry summer. There is no outlet to 

 these lochs, so that the hollow in the peat cannot be accounted for by the scour of a 

 large stream. Such basins in the peat, occupied by small lochs, are by no means 

 uncommon ; I have observed many examples in the hilly districts of Scotland and on 

 the Pennine Chain in England, but the present example is of interest on account of the 

 peat upon which the loch rests, containing, first an arctic flora and then a buried 

 forest, thus showing that extensive and prolonged changes have occurred during the 

 peat growth. 



(b) The Ridge in the Centre of the Mainland to the North of Weisdale Voe. — From 

 Weisdale Voe to Dales Voe a band of limestone traverses the gneissose rocks of the 

 centre of the mainland for a distance of 12 miles N. and S., and gives rise to a range of 

 smooth rounded hills with their longer axes all pointing N. and S. None of the hills 

 reach 1000 feet, most of them ranging from 500 feet to 921 feet on Scalla Field. 



Sections were taken on Weisdale Hill, North Mid Field, Scalla Field, Gunti Field, 

 ami Fielandringa. All these hills have a thick mantle of peat which has been furrowed 



