MICROPALÆONTOLOGY OF POSTGLACIAL DEPOSITS. 467 
The beds are as follows :— 
A. 200 cm. Sphagnum peat, closely intermingled with Eriophorum vagi- 
natum remains ; lowest dark brown, H 8-9, forming a transition to 
B. 90 cm. Peat, most resembling Carew peat, very compressed and 
difficult to force with the hore ; seeds of Menyanthes. 
C. (at 290 em.) Green sand. 
TEXT-FIG, 9. 
0 10 20 30 40 50 60 70 80 90 100°. 
—0— Alnus. —O— Betula. —e— Pinus. .——— Ulmus. 
Quercus. -------- Tilia. --g-- Corylus. 
Ordnance Survey of Scotland, Sheet 80.) 
Lewis (ii. 1906, p. 338) studied exactly the same moss, and he, too, 
remarks that the layers are not well-defined. In the lowest layer he saw 
twigs of Betula alba. 
The three diagrams from Skye (text-figs. 7, 8, and 9) agree chiefly in three 
respects: 1, the dominance of birch-pollen in the oldest layers; 2, the sudden 
appearance of alder-pollen, which very soon attains a great frequency ; 3, the 
low frequency of pine-pollen. 
In Part II. p. 353, Lewis says: “No trace of Arctic plants has hitherto 
been found either at the base or elsewhere in the Hebridean peat, thus 
