Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 82

in particular occurs also. C. capillaris is also noticeable, as is C.
microglochin to some extent. C. panicea, Juncus alpinus and Tha-
lictrum alpinum are also more conspicuous than in sociation no. 39.
The occurrence of these species undisputably indicates that the
mýri is eutrophic, and on this premise I define this as an indivi-
dual sociation, which should perhaps have been better associated
in name with Carex capillaris than Menyanthes. The biological
spectrum distinguishes itself from sociation 39 in the total absence
here of Ch percentage, whereas the HH percentage becomes quite
high. The surface had a slight slope, flat or pattemed by fine low
mounds. When I examined it in July of 1950 it was dry after a
long dry season, but the topography showed that the area is usual-
ly quite wet. Peat formation appeared to be considerable.
At Mjóanes in Fljótsdalshérað I saw this sociation cover a fairly
extensive area. The terrain was pattemed with low, flat mounds,
rather wet with abundant bog iron in hollows. Most of the species
were the same. C. capillaris was quite common and C. dioica was
also quite noticeable.
41. C. nigra — C. Bigelowii soeiation
(Tab. XIx A-B 1)
The only observation is from Húsafell in Borgarfjörður near the
highland border. The mýri where the analysis was made is at the
foot of a hill, slightly sloping and rather dry. The two character
species are about equal with respect to covering, but C. Bigelowii
covers somewhat more. As will be described later C. Bigelowii re-
places C. nigra in highland areas and we may therefore expect
this sociation to be a transitional form between these two associa-
tions. It has, however, a closer relationship with the C. nigra mýri.
Nothing will be stated with certainty about the distribution, but
it may be assumed to occur widely at altitude levels which dis-
tinguish between the character species, where topography allows.
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