806 MR FRANCIS J. LEWIS 



areas have been entirely cleared. I was assured by one of the oldest inhabitants, who 

 is a native of the island, that one large area about half a mile across was cleared more than 

 150 years ago. No peat is to be found here now; the rock is exposed over large areas, 

 with patches of thin vegetation consisting of Calluna vulgaris, Nardus striata, Juncus 

 squarrosus, Festuca ovina var. vivipara, Empetrum nigrum, Potentilla tormentilla, 

 with Viola palustris, Hydrocotyle europseus, and a small quantity of Sphagnum in 

 damper places. 



The most striking feature of the peat deposits is the fact that the remains of birch 

 trees occur in nearly all places where the peat is more than 8 feet in depth. The 

 general stratification is the same as that described from Shetland Mainland, with some 

 additional features. A section near Flick Lochs will illustrate the complete series : — 



1. Recent peat : — Sphagnum sps., Erioplwrum vaginatum, Calluna vulgaris. 



2. Juniperus communis : — A very distinct layer found in all the sections at Flick Lochs and Overfandel 



Lochs. 



3. Erioplwrum vaginatum forming peat. 



4. Betula glutinosa, Fries. :— The remains of small hushes. 



5. Scirpus ceespitosus ? : — Peat much decomposed, with a few nutlets of Carex sp. 



6. Empetrum nigrum : — Potentilla tormentilla, Empetrum seeds, Calluna, Sphagnum sps. 



7. Betula verrucosa : — Pieces of fairly well-grown trunks up to 11 inches in diameter, Pyrus Aucuparia. 



8. Salix sp. : — Small creeping willow with hark and buds resembling Salix herbacea, but no leaves 



found. 



9. Structureless peat. 

 10. Fine sand and gravel. 



Stratum 7 here occupies the same horizon and bears the same relation to the other 

 strata as it does on Shetland Mainland. The juniper in stratum 2 is a new feature in 

 the Shetland peat, and occupies the same position as the Upper Forest of Pinus 

 sylvestris in the south of Scotland. It is very curious that no trace of woodland con- 

 ditions has been met with on the Mainland subsequent to the Lower Forest. The 

 much greater height of the hills here may have a bearing upon the point, the highest 

 hills round which sections have been taken on the Mainland being only 800 feet. On 

 the other hand, Foula is more wind-swept and more unfavourable for tree growth than 

 the Mainland. The only hill in Shetland approaching Foula in height is Eonas Hill 

 (1475 feet), and it would be interesting to see if strata 2 and 4 make their appearance 

 in the peat there ; but so far as I have been able to find, peat is thin and scarce in the 

 area immediately at the base of that hill. Without attempting to draw any definite 

 conclusions from a few sections in a small area, it may yet be pointed out that the 

 position of juniper in stratum 2 and birch in stratum 4 exactly corresponds to the two 

 layers of the Upper Forest met with in the Scottish Highlands (2), separated by 

 Sphagnum, Eriophorum, and Scirpus peat. Like the rest of Shetland, Foula is tree- 

 less, and even planted trees are absent. About ten or fifteen years ago a small piece of 

 land a lew yards square was planted, and the bushes protected by a stone wall 4|- feet 

 high. The chief species are : Betula alba, Sambucus nigra, Pyrus Aucuparia, Acer 

 carnpestic, A/uus glutinosa, Salix sp., probably alba. Although most of these are 



