Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 62

lyses are available I am unable to deal more comprehensively with
the sociation.
The C. rostrata — C. nigra sociation grows where the flói is
fairly dry, at least in the driest areas of the C. rostrata flói. Usu-
ally the terrain is not completely flat and there are often traces
of mound patterns. The E percentage here is high, Ch % is notice-
able in parts, H percentage is low, whereas the HH percentage is
rather high.
Analysis 9 is made at Brjánslækur in Barðaströnd. The terrain
is rather wet there for this sociation and finely mound pattemed.
The sociation extends over a fairly large area. Empetrum and V.
uliginosum grow on the mounds and red Drosera patches occur in
the moss. I have not seen many mire patches here in Iceland
which are more reminiscent of the Scandinavian mossar. Or per-
haps rather Myrvidd-mjukmatt samhállen (Sjörs, 1948 p. 128).
The other analyses are made to the south of Kaldidalur at the
Bnmnar area, where there are extensive C. rostrata flói tracts main-
ly covered with this sociation except for the wettest parts, where
C. rostrata — C. rariflora — C. chordorrhiza sociation 25 occurs.
These two sociations may be regarded as sole dominants in flói
tracts in these parts.
31. The C. rostrata — C. nigra — Equisetum palustre sociation
(Tah. VI x A-B 10)
The only analysis of this sociation is from Gíslholt in Holt, where
this sociation is common and covers large areas. Like some other
sociation of the C. rostrata flói it approximates the mýri both in
terms of vegetation and topography. The surface is more mound
pattemed than in a typical flói, but less so than the mýri, and in
most places the slope is such that the water is not altogether stag-
nant. There is considerable moss and Sphagnum occurs. The flói
is also rather dry. What indicates mýri is the high frequency of
C. nigra and Equisetum palustre, both of which are noticeable in
physiognomy and covering, but on the other hand there are the
typical flói species in addition to C. rostrata, both Comarum palustre
and Menyanthes trifoliata. E. angustifolium has considerable fre-
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