The Botany of Iceland - 01.12.1930, Page 36

26
H. M0LHOLM HANSEN
H Knautia arvensis Th Polygonum persicaria
Th Lamium intermedium HH Potamogeton natans
H Lathyrus pratensis Ph Rosa canina
Th Linum catharticum Ch — spinossissima
G Listera ovata HH Ruppia maritima
H Litorella uniflora H Sagina subulata
H Lychnis tlos cuculi H Sangvisorba officinalis
Th Myosotis hispida Ch Sedum acre
Th — micrantha Th Senecio vulgaris
Th versicolor Th Sisymbrium sophia
HH Myriophyllum verticillatum HH Sparganium minimum
Ophioglossum vulgatum H Succisa pratensis
G Orchis latifolius H Valeriana officinalis
H Phleum pratense HH Veronica anagallis
H Plantago lanceolata H Vicia sepium
Polypodium vulgare H Viola silvestris
HH Polygonum amphibium Th — tricolor
HH Zannichellia palustris.
On the basis of particulars as to the proportion of each species
in the floras of the above-mentioned countries, the Icelandic species
were referred to one of the 7 species groups. While it is comparatively
easy to place the species in the A or E groups, as this is only a
question of ascertaining whether the main distribution of the species
is above or below, north or south of three limits, the 20 % Ch bio-
chore, a subdivision at the outset necessitates the selection of a pa-
rallel of latitude, to the north of which the species do not occur.
At each species group is stated the parallel of latitude selected as
the upper limit of the species. In order to gain a comprehensive
view of the extent to which it has been possible to gather the
species into groups expressing adaptation to the arctic climate, the
following conditions have been reviewed: — 1) The presence of the
species groups in the floras of the different countries, 2) the distri-
bution of the groups in Iceland, and 3) the content of Raunkiær’s
life forms in each group.
I. In table 4 are given the individual countries examined, be-
ginning with those that are most arctic in character, as Ellesmere-
land, North Greenland, and Spitsbergen, and ending with the most
temperate. In the íirst column is stated the number of species which
the country in question has in common with Iceland. The next
two columns state how many of these species, comrnon to both,
belong to the A- and E-groups, and the last columns give particulars
of the sub-groups.