464 MR. G, ERDTMAN: STUDIES IN THE 
The lowest layer of this moss is probably synchronous with the A-zone 
(pine-stools, low frequency of alder-pollen), in which case the layer with the 
greatest amount of Alnus pollen would best correspond with that from which 
sample 6, moss No. 4, was taken. 
Pollen of Chenopodiacere, which is frequently met with in mosses near the 
sea (cf. Erdtman, 1921, p. 135 ; Halden, 1922), is recorded from sample 11, 
guard-cells from the stomata of pine needles from samples 9-11. 
Some Observations from Smaller Peat-deposits. 
Prat Mosses Nos. 6 a,b,e,d. (Text-fig. 6.) 
From the hillsides around Loch a’ Chroisg, N.W. of Lubmore and about 
265 m. above sea-level, a series of samples was taken from a bog with Carer 
rostrata, Eriophorum polystachion, Juncus supinus, Narthecium ossifragum, 
Pinguicula vulgaris, Potamogeton polygonifolius, ete. The peat varied in 
thickness from 150-200 cm. A sample taken immediately above the rocky 
bed of the bog, when analysed, showed the following percentages : 
Alnus, sporadie (1:3), Betula, 98 (98), Pinus, 2 (07) : * Corylus,” 2:8 (4). 
The figures in brackets are taken from sample 2, moss No. 4, and are given 
for comparison. Of course these samples are synchronous, and, if so, this 
bog must be considerably later than the peat-deposits described above. 
TEXT-FIG, 6. 
20 30 40 50 60 70° 
6 b ^ Ld À. | 450 | 
n 650 
6c —d —___{ —1 
\ 700 
6dl à e pf — S 
—pn-— Alnus. —o— Betula. —e— Pinus. ren Ulmus. 
—— Quercus, —-------- Tilia, --m-- Corylus, 
The diagram (fig. 6) shows three pollen-spectra from the hills N. and N.W. 
of Achnasheen. 65 was collected about 10 m. N.E. of Allt Achad na Sine, 
450 m. above sea-level: Ge about 550 m. N.W. of the point 2101 at the 
name ** Creagan nan Laogh” (650 m. above sea-level), and 6d on “Sail” 
and Tuim Bhain (about 400 m. W. of “N” in “Sail,” and 700 m. above sea- 
level). The samples are taken from the bases of mounds of peat, the relies 
of the shallow bed of peat which once covered the whole slope. Their pollen 
character seems best to correspond with a zone somewhat younger than the 
A-zone (cf. sample 5, moss No. 1, and sample 5, moss No. 2). In sample 
Ge there occurred a single lime pollen-grain. No specimens were taken 
from a greater altitude than these, but the presence of pollen-grains alone 
is not sufficient evidence on which to arrive at a definite conclusion with 
regard to the vertical distribution of trees. 
