Rit (Vísindafélag Íslendinga) - 01.06.1975, Page 63
quency but limited growtb.. I have not seen this sociation elsewhere
in the country.
32. The C. rostrata — C. Lyngbyei sociation
(Tab. V A-B 13 and Tab. VI x A-B 1)
There are only two analyses, V. 13 from Kaldidalur and VIx 1
from Húsafell in Borgarfjörður. Both were taken at a considerable
altitude above sea level. The Húsafell analysis is hardly typical,
however, since various flói plants are absent there, when in addi-
tion the hybrid C. Lyngbyei x C. Bigelowii replaces C. Lyngbyei.
At Kaldidalur, on the other hand the flói species Comarum palustre
and Menyanthes trifoliata are noticeable. Nothing is to be said
about the distribution of this sociation, but it may be assumed to
occur in lower parts of the highland. However I have observed it
m Melrakkaslétta where C. rariflora was significantly conspicuous.
The observation sites were both in a clayish wet flói. At Kaldidalur
the analysis was made in the vicinity of an E. angustifolium — C.
Lyngbyei sociation 14 (Tab. IV. 7), but it could hardly be deter-
mined what the actual cause was for the difference in vegetation,
smce the observation sites were so close together.
33. C. rostrata — Calamagrostis neglecta sociation
(Tab. VI A-B 7)
This sociation was only observed at Nauthagi, and the analysis
Was made near V. 14. The topography there is such that a narrow
C. rostrata belt is alongside a brook, beyond which C. Lyngbyei
commences. Apart from the character species Equisetum fluviatile,
C. Lyngbyei, and C. rariflora are noticeable in the wettest parts.
e. Tlie Carex cbordorrhiza flói — Caricétum cbordorrhizae
Carex chordorrhiza is one of the typical Icelandic flói plants. It
ls a character species together with others, i.e. E. angustifohum
arid C. rostrata in various sociations and occurs in many more. In
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