The Botany of Iceland - 01.12.1945, Blaðsíða 86

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STEINDÓR STEINDÓRSSON
fairly distinctly that we are here concerned with two kinds of snow-
patches, those rich in species, associations 1-8, in which the snow-cover-
ing is not very long-lasting, and those poor in species, associations 9-11,
in which the snow-covering is particularly long-lasting, so that it will
to some extent impede the growth of the plants.
10. Eriophorum Scheuchzeri—Carex lagopina-Ass.
(Tab. XII. A-B, 7-8).
It is with some hesitation that I refer this association to the snow-
patch formation, for one of its character species belongs to the most
typical plants of damp soil. On the other hand, typical snow-patch
species are present, and the conditions in the locality show very clearly
that the snow-covering is both thick and long-lasting. The most con-
spicuous species are Eriophorum Scheuchzeri, Carex lagopina, Cerastium
trigynum, Salix herbaceai, and Epilobium anagallidifolium. Analysis
XII, 7 was carried out on Eyjabakkar at an altitude of c. 700 m above
sea-level, in a small narrow ravine through which there runs a brook.
The surface was level and fairly damp. The phanerogamous vegetation
was scattered, and a great quantity of moss, notably Philonotis, was
found in the ground vegetation. Analysis XII, 8 is from Síðumanna-
afrjettur, from a similar locality to that of XII, 7. Of the species re-
presented in the first analysis C. lagopina has become much less con-
spicuous, while Carex rufina has appeared and is here among the
dominants in addition to Eriophorum. This variant rich in C. rufina
was occasionally encountered by me, thus on Síðumannaafrjettur, at
Þúfuver near Þjórsá, and at Háls on Snæfellsöræfi. The main association
is fairly widely distributed under the conditions outlined here, but never
covers any large areas. The terrains in which it is found distinctly show
that it is associated with the snow-patch, but the damp soil gives it a
special position, so that as to species composition it forms a kind of
transition to the dý vegetation.
11. Catabrosa algida—Cerastium trigynum-Ass. (Tab. XII. A-B, 9).
In addition to the character species, Salix herbacea, Equisetum
arvense, and Carex lagopina are dominant species, furthermore Saxi-
fraga stellaris and Koenigia islandica are of importance. The only
analysis at hand was taken on Eyjafell on Snæfellsöræfi at an altitude
of c. 650 m. The phanerogamous vegetation is open, and the Anthelia