The Botany of Iceland - 01.12.1945, Síða 57

THE VEGETATION OF CENTRAL ICELAND
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Sphagnum teres. The phanerogamous vegetation was rather scattered;
the following species were the most conspicuous: Carex rariflora1, Erio-
phorum polystachyum, and Salix glauca; in addition there occurred
considerable numbers of Carex rigida, Empetrum nigrum, Vaccinium
uliginosum, Saxifraga Hirculus, and Pedicularis flammea. One of the
moss samples was taken in the dampest place of the mýri, it contained:
Sphagnum teres, Gymnocybe palustris, Camptothecium trichoides, and
Hypnum uncinatum. The other sample was derived from a much drier
place, and contained: Sphagnum teres, Hypnum uncinatum, Martinel-
lia curta, Onchophorus Wahlenbergii, and Calliergon stramineum. I
did not encounter this type of mýri in other parts of the highland.
io. Ridge mýri. (Tab. VI. A-B, 4-5).
On Síðumannaafrjettur there occurs a widely distributed type of
mýri which differs in character from the other types of mýri seen by
me in the highland as well as in the lowland. I have mentioned above
the formation of low ridges with lakelets or patches of flói behind them,
which are found both in Fagridalur and on Síðumannaafrjettur, where
the surface shows a considerable inclination. The mýri here called by
me ridge mýri (Icelandic: rimamýri) is a closely related formation, it
is found where the surface is very slightly inclined, so that the inclina-
tion is hardly noticed except on close examination. In this type of mýri
level depressions with a poor moss vegetation altemate with low knolly
ridges, somewhat more elevated, with an abundant moss vegetation. In
the depressions Carex rariflora it mostly the dominant species, in some
places, however, it is Carex rostrata, with an admixture of C. Lyngbyei
and Calamagrostis neglecta (see further Tab. VI, 4). On the ridges
C. Goodenoughii, C. rigida, and Equisetum palustre predominate, often
abundantly mixed with Salix glauca (cf. Tab. VI, 5). Along the
edges of the ridges C. rariflora and C. Goodenoughii occur in about
equal numbers, while Equisetum is, as a rule, absent. I have no analysis
from this transitional form. It appears from what has been stated above
that we are here concerned with a kind of complex of formations; on
the ridges there occurs a mýri formation (C. Goodenoughii—Equis.
palustre-association), but in the depressions a typical flói (C. rariflora
association). In all parts of Síðumannaafrjettur where this type of mýri
is found, its species composition seems to be very uniform.
I do not know this type of mýri from any other place. I assume
that we are here concerned with a kind of transitional form between