MICROPALÆONTOLOGY OF POSTGLACIAL DEPOSITS. 461 
The view has been put forward that the remains of pollen-grains embedded 
in peat would differ from those embedded in mud (cf. Malmström, 1923 
p. 147*). If this always were so, the reliability of the diagrams would be 
considerably’ reduced. I have already discussed this question (1921), and 
my opinion is that the pollen-spectra are influenced very slightly, or not at 
all, by the matrix in which the pollen-grains are embedded. 
In order to explore this problem further, a series of samples was collected 
from genuine hill-peat only 200 m. from the peat moss just described (No. 2). 
The furrows caused by erosion reach a depth of 2 m. in this peat, and pine- 
stools occasionally occur. This moss seems to have originated at the same 
time as moss No. 2, because the pollen-spectrum of sample 5 is in accurate 
correspondence with the spectrum of the lowest gyttja stratum in No. 2. 
There seems to be no doubt as to the identity of the horizon of sample 3 
(with its well-defined Pinus-pollen maximum) with the A-zone. At what 
time the formation of peat ceased cannot be stated owing to the scantiness 
of the material for study. 
PEaAT Moss No. 4. 
Trxr-ric. 4. 
20 30 40 50 60 70 80 90 100 v, 
1 
2 
3 
4 
L— | 
MW De 
Ève 5 
" > oe , 
— 0 — Alnus. —o— Betula. —e— Pinus me Ulmus. 
———— Quercus. —-— ------- Tilia. --m-- Corylus. 
Situation : A little W. of the west end of Loch a’ Chroisg, 110 m. N.E. of 
the point of the map where the road Achnasheen-Kinlochewe crosses Allt 
na Féithe Baine ; altitude above sea-level about 200 m. 
This moss is quite a small one, resting on sand. The surface is clothed 
with a dense carpet of Calluna, Erica, Myrica, Potentilla erecta, Scirpus 
* Malmström shows that in lake deposits the frequency of conifer pollen is considerably 
greater in sediments formed very near the shore than in sediments deposited in deep water. 
This difference might, however, be of but little importance when dealing with small, 
shallow lochs or mere hollows in the peat filled by water, 
