The Botany of Iceland - 01.12.1912, Síða 141

MARINK ALGAL VEGETATION
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the sunimer. Manjr pools filled with decaying and dying algæ.”
The occurrence of algæ so high up can be imagined onljr on a
very exposed coast facing the open sea, and even there it would
be exceptional.
The dominant species of the vegetation in these high-lying pools
consisted of Fucus in/lalas f. linearis. Intermixed occurred Chœto-
morpha Melagoninm — which I never before had seen so high above
sea-level — Acrosiphonia sp., Dictyosiphon foeniculaceus, Pylaiella
littoralis and Enteromorpha intestinalis f. typica. The undergrowth
consisted of Hildenbrandia rosea.
In another somewhat elevated and exposed place in the vicinity
of Vattarnes, a number of small pools were found just helow the
Verrucaria maura-belt. Hildenbrandia and Verrucaria mucosa grew
on stones at tlie bottom of tliese pools; in addition, Fucus inftatus
f. linearis occurred fairly abundantly, although dying in the pools,
which were deíícient in water.
The lower pools in the upper littoral zone have a much more
luxuriant vegetation. Here various littoral and semi-littoral species
can grow in fair abundance. The water in these pools is replenished
at each high-water, so here, the plants exist under fairly favourable
conditions. The following species may occur dominantly or abun-
dantly: — Fucus in/lalus f. linearis, Halosaccion ramentaceum, Mono-
slroma fuscum, Enteromorpha intestinalis, Monostroma Greuillei, Dic-
tyosiphon foeniculaceus and Castagnea uirescens.
Many species are found growing scattered, of whieh the fol-
lowing are most frequently met with: —
Polysiphonia urceolata.
Porphyra miniata.
Rhodoniela lycopodioides.
Rhodymenia palmata.
Chorda Filum.
C.hordaria flagelliformis.
Coilodesme hulligera.1
Ectocarpus confervoides.
Elachista fucicola.
Phyllitis fascia.
Pylaiella litoralis.
Scytosiphon Lomentaria.
Chætomorpha Melagonium.
C. tortuosa.
Cladophora gracilis.
Monostroma undulatum.
Ulothrix llacca.
Urospora Wormskioldii.
The under-vegetation often consists of Ralfsia deusta, Litho-
thamnion circumscriptum and Hildenbrandia rosea.
Taken on the whole, the majority of the littoral species un-
doubtedly may be met with in the pools, and it should be especially
1 It may be observed, as regards Coilodesme, that it is the more inflated
the lower the water is in the pools.