710 MR FRANCIS J. LEWIS 
denudation of the peat be seen in a more striking form, the whole of the peat area being 
intersected by deep channels, whilst the larger burns have cut through the peat some 
distance into the underlying clay. (Fig. 11.) The boundary of the peat and Nardus 
vegetation forms an irregular line along the hill-sides, presenting the general features 
found on the hills of the Weardale watersheds (10). Long tongues of dark heath- 
covered peat frequently stretch into the surrounding Nardus areas, and outliers of peat 
oceur quite low down on the hill-sides. These are islands of peat which have been left 
behind by the main peat mass as it retreated up the hill-sides, owing to denudation. 
Many of the hill-sides which are still clothed with peat are very steep, and it is difficult 
to see how the peat could have accumulated there under present conditions. The peat 
attains a depth of 16 feet in some places, but is more usually about 7 or 8 feet in 
thickness. Owing to its channelled condition and situation on steep hill-sides it is 
generally dry, and the plant remains are better preserved than elsewhere. 
The mosses rest upon glacial deposits consisting of stiff gray clay, containing many 
stones and occasionally small nests of sand. All the sections agree in showing an 
absence of any great development of woodland, but a little shrubby birch appears in 
some places in the peat. 
The plant-beds exposed at the same horizons in different sections agree with one 
another fairly well, but there is rather more variation than was found to be the case in 
the flat mosses previously described. This was perhaps to be expected, as the factors of 
aspect, degree of inclination of the ground, and altitude would come in on these hill-top 
mosses and tend to produce a vegetation which would vary much more at any one 
time, and prevent the growth of a uniform plant association such as we find developed 
over a flat low level moss. The general sequence of vegetation appears to have been 
the same all over the Moorfoot Hills, but some of the beds found to be present in one 
place are absent in others. 
The lower edge of the mantle of peat in most places contains a basal layer of Betula 
alba of shrubby size mixed with Calluna, whilst in other places this growth is replaced 
by small Salices. The layers of peat immediately above this are formed chiefly of 
Eriophorum vaginatum, which, in the peat situated at higher elevations, rests directly 
upon the clay. The peat resting upon the Eriophorum layer is formed of Hmpetrum 
mgrum, and this layer has been found to be well developed in all the sections. This 
again is overlaid by Hriophorum vaginatum peat, on the higher lying ground. Later, 
this is replaced by peat containing much Calluna vulgaris, which above yields place to 
Scirpus and Sphagnum mixed with scanty Hriophorum vaginatum. 
The four following sections show the variations met with in different positions, 
together with the plant remains recognised from each layer :— 
