Náttúrufræðingurinn - 1949, Blaðsíða 29

FLÓRUN Ý JUN GAR 1948
121
a£ því að hún vex um miklu stærra svæði, en líklega er hún einna
algengust á svæðinu milli Mýrdalssands og Fljótshlíðar. Slíkt styður
óneitanlega tilgátuna um flutning þeirra með mönnum.
Eins og þegar er tekið fram, er hér einungis unt tilgátu að ræða.
Og gildir hér sent annars staðar iiið fornkveðna, að hafa skal það,
er sannara reynist.
SUMMARY
In this article is discussed the distribrition o£ 52 Icelandic plants, which are either
rare or have a peculiar distribution in certain parts of the country. Three new accident-
ally introduced plants are also mentioned.
In the latter part of the article it is mentioned, that there are 5 districts in the
country, each forming a kind o£ plant centre, and that at least 100 Icelandic plants
sliow a marked centric distribution, cither uni-, bi- or tricentric. Two species, Botry-
chium lanceolatum and Isoetes lacustris, growing in tlie South-west o£ Iceland are dis-
cussecl and the conjecture put forward, that they have survived in Iceland during the last
glaciation period. Further, 7 species are discussed: Lychnis flos cuculi, Plantago lance-
olatum, Succisa pratensis, Lathyrus pratensis, Vicia sepium, Carex flacca, and Glyceria
fluitans, the central distribution o£ which is to be found in the central part o£ the
South of Iceland, chiefly south of Eyjafjalla- and Mýrdais-jökuls. The opinion is ex-
piessed, that they have been imported into the country by human agency, perhaps by
hermits from the British Isles, who stayed in Iceland before its settlement by Norse-
mcn, as all the species seeni to be ntore comrnon in the British Isles, than in Scandin-
avia. The article is accompanied by rnaps showing the distribution of the species in
question.