Rit (Vísindafélag Íslendinga) - 01.06.1975, Síða 146

As may be gathered from the list a total of 48 phanerogamous
species have been found in those 23 cold springs, but quite a few
of them may belong to adjacent sociations. The munher of species
in each cold spring varied from 4-12. The average was 7. It is
notable that only 9 species were found in 6 or more places, that
is more than a quarter of the areas examined. The most common
species were found in 11 places, but there were only two of them,
Cardamine pratensis and Epilobimn alsinifolium. Other two, Saxi-
fraga stellaris and Montia lamprosperma were found in 10 places
and out of the other 37. 18 were only encountered in one locality
and 7 in two localities. It may be gathered from this that it is rather
coincidental which species occur in the cold springs.
Among 9 the most common species there are only three about
which it can be stated with certainty that they occur more com-
monly in cold springs than in other types of mire vegetation, and
the two first mentioned do not occur in highland regions. In my
paper 1945 I discussed two types of cold spring vegetation on the
basis of my own experience and research by Dr. Helgi Jónsson.
On the one hand the lowland type dominated by Epilobium species,
Montia and Catabrosa aquatica, and on the other hand the alpine
type in which all these species are absent, while Cerastium cerasto-
ides, Deschampsia alpina, Eriophorum Scheuchzeri and various
Saxifraga are the commonest species. And I see no reason now to
reconsider that conclusion.
E. J A Ð A R — Tlie mire border
Between the mire and the dry plant communities, heath, grass-
land or even melur (gravel flat) there occurs as a rule a special
formation called jaðar (border). This formation was first described
by Hansen 1930 p. 179.
The jaðar (border) can take many different forms; most com-
monly, however, it constitutes a narrow strip, only a few metres
in width. It sometimes forms a tall mound-ridge on the border of
heaths, in which case a clay flat often occurs heath-wards of the
border. This is most noticeable when the heath or even gravel flat
is somewhat more elevated than the mire tract which is probably
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