The Botany of Iceland - 01.12.1930, Side 109
STUDIES ON THE VEGETAI'ION OF ICELAND
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Silene acaulis, Luzula arcuata, Arabis petrœa, Aira alpina, Oxyria
digyna, Salix herbacea, and Saxifraga rivularis.” “At higher levels
only sonie few individuals of Salix herbacea, Sibbaldia procumbens,
and Aira alpina were met with.”
“In the lower fell-field the phanerogams play a much more pro-
minent part”. The most frequent plants here are: Salix lierbacea,
Saxifraga rivularis, Sibbaldia procumbens, Oxyria digyna, RanuncUlus
glacialis, Pedicularis ftammea, Luzuta arcuata, and Epilobium ana-
gallidifolium.
“The following occur frequently: Silene acaulis, Carex rigida,
Polygonum viviparum, Empetrum nigrum, Loiseleuria procumbens,
Cassiope hypnoides, Armeria maritima, Arabis petrœa, Veronica alpina,
Thalíctrum alpinum, Luzula spicata, Juncus trifidus, Saxifrciga cœspi-
tosa, Alchemilla alpina, Cerastium alpinum, Aira alpina, Thymus Ser-
pyllum, Saxifraga oppositifotia, Gnaphalium supinum, Cerastium tri-
gynum, Poa glauca.”
“The less frequent are: fíetula nana, Dryas octopetala, Papaver
radicatum, Salix glauca, Trisetum subspicatum, Poa alpina, Pyrola
minor, Saxifraga nivalis, S. hypnoides, Galium silvestre, Ranunculus
acer, Cystopteris fragilis. Of rarer occurrence are: Taraxacum lœvi-
gatum, Rumex acetosa, Rhodiola rosea, Carex lagopina, Potentilla
verna, Luzula multiftora, Festuca ovina.”
III. The Anthelia crust. “On gravelly, clayey, or stony soil,
in the mountains, at an altitude of 300—-700 m., increasing with
the height, a grey crust, dispersed in patches, is very often met
with. It is formed exclusively of Anthelia nivalis. Interspersed
with it I sometimes found Grimmia hypnoides, G. ericoides and Salix
herbacea. This Anthelietum often borders on the Salix herbacea
depressions. Transitional forms between the Anthelia and the Salix
herbacea vegetation are occasionally found.”
IV. The Salix herbacea and Sibbaldia vegetation.
• • occupies the aforementioned depressions where the clajrey strata
cover the subsoil. The main dispersal of this vegetation lies be-
tween 300 and 600 m. above sea level. In the lower part there is
often a strong admixture of the elements of the heather moor, and
at an altitude of over 600 m. it passes into the moss vegetation.
An undergrowth formed of mosses is nearly always present.” “Very
often it is formed of Grimmia hypnoides and occasionally of An-
thelia nivalis.” “Not a few of the phanerogams of the fell-field are
interspersed in the Salix and Sibbaldia patches. As far as I could
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