The Island of Lewis is usually described as a western outlier of the Fundamental Gneiss, but this cannot be regarded as a description in any sense, for the gneisses of Lewis present many features different from those which characterise the Lewisian of the adjacent mainland, and it is evident that they present varied phenomena of interest and importance meriting the systematic study which has so long been denied them. The earliest account of the rocks of the island is contained in Macculloch's “Western Isles” and in his letters. In both he describes the gneiss, and in the letters he figures the contortions seen in some exposures. Murchison and the Geikies have touched on the glacial and solid geology of Lewis in papers in the Quarterly Journal of the Geological Society ,1 and in the Transactions of the Geological Society of Edinburgh there is a description of the conglomerate by Morrison of Carrbridge.2 The most recent and the most systematic examination of the gneiss was made by Drs. Peach and Horne in 1911, and their results were summarised for the Dundee meeting of the British Association of last year.3 The material for these notes was collected on sporadic excursions made in company with and under the guidance of Mr. W. J. Gibson, of Stornoway, and in working it up I have been indebted to Mr. Tyrrell for useful suggestions. The area studied is roughly bounded by the limits of the patch of newer sedimentaries which encircle Stornoway Harbour, and stretch northwards just This 250-word extract was created in the absence of an abstract