Fuly 8, 1886] 
than from south to north. In keeping with the same are 
the variations of the flora. 
The plants of Norway may be divided into certain 
groups of species, the species belonging to the same 
group having a somewhat similar extension, whilst each 
of these groups of species is confined to special climato- 
logical conditions, and is only found in those parts where 
such prevail. The Norwegian flora is in the main mono- 
tonous. On the mountains large areas are covered with 
only a few lichens, mosses, and heather, or copses of 
dwarf birch, juniper, and willows ; lower down the forests 
are formed of birch, fir, and spruce, and have a monoto- 
nous flora, viz., heather and lichen in the fir forests, 
“blue” berries and a few kinds of moss in the spruce 
forests, whilst the west coast is covered with heather, 
and the numerous marshes with a vegetation, poor in 
species, of a few mosses and Carices. 
But in spite of this general monotony of the flora of 
the mountain wastes, with their grayish-yellow lichens, 
grayish-green and green copses of willows or dwarf 
birch, there are certain places, particularly on slaty ground, 
where a rich vegetation may be found. It consists of 
small perennial plants some inches in height, and which 
are particularly distinguished by their copiousness of 
flowers, which are very large in proportion to the size of 
the plant, and have very pure and lovely colours. Outside 
Norway we also encounter these plants in Arctic regions, 
and the Alpine flora of these slaty tracts is therefore of 
Arctic character. But not allslate mountains have such 
a varying flora. 
the mild winters, when the temperature frequently changes, 
destructive to these plants, which shoot at a very low 
degree of heat. It is for this reason that, when we mark 
those places on the map which have a rich Alpine flora, | 
they lie scattered as oases over the land with great | 
spaces between them, but always sheltered from the sea- 
winds, z.e. on the east or north-east side of the highest 
mountains and greatest glaciers, which act as barriers 
against the mild climate of the coast. In these places 
the botanist may fancy himself transferred to Spitzbergen 
or North Greenland ; he finds the principal plants en- 
countered there, and if we follow the Arctic flora to 
Spitzbergen we find that here also it shuns the sea, and 
is most copious in the bottom of the fjords. 
In the lower districts, sheltered from the open sea, we 
find in favourable spots another group of plants which 
also shun the coast, and which thrive on loose slates and 
warm limestone cliffs, or in screes of different kinds of 
rock, under precipitous mountains, facing the sun. These 
screes are generally full of bare boulders at the bottom, 
but in the finer debris higher up grows a wreath of green 
underwood, formed of tender deciduous trees and shrubs, 
hazel, elm, lime, maple, dog-roses, Sorvdus Aria, Prunus 
avium, wild apple, &c., as well as a number of highly- 
scented Labiatz, several Papilionacez, grasses, and a 
great number of other plants, together forming that part 
of the Norwegian lowland flora which shuns the open sea- 
coast, and prefers the fjords and the sunny valleys. 
even this flora has a scattered extension. It is richest in 
-the tracts around Christiania, and becomes poorer west- 
wards along the coast, disappearing almost entirely on 
the coasts of the province of Bergen ; but at the bottom 
of the Sogne and Hardanger, and along the Throndhjem 
fjords we find the same flora, and that in spite of these 
parts being entirely separated by enormous mountains. 
Near the open sea the flora becomes poorer in species, 
most of those characteristic of the interior disappearing, 
whilst their number is not by far made up by those be- 
longing to the coast. Here we shall only name a few of 
the coast plants, such as the holly, the ivy, and the foxglove, 
whilst in place of the Prémula veris of East Norway we 
have the Primula acaulis of the west coast. In the woodless 
tracts of the coast the heather predominates, and besides 
the ordinary common one we find two other species. ! 
The coast climate is, in consequence of | 
But |} 
NALEKE 
Bape) 
This group of plants belongs exclusively to the south and 
west coasts, and is hardly found north of the Throndhjem 
fjord. Most of its species are not found near Christiania, 
but they reappear in the south of Sweden. Some, how- 
ever, are in Scandinavia only found on the west coast of 
Norway, and we must travel to the Faroe Islands, 
Scotland, England, and Belgium to re-encounter them. 
We have thus seen that the Norwegian flora consists of 
groups of species which make different demands as to 
climate. If we were to colour a map according to the 
places where certain groups are most copious, we should 
at once discover that they had a scattered distribution. 
We should find the same colour here and there, in 
smaller or larger patches, but those of the same colour 
would be separated by great spaces of a different tint. 
At one time botanists were satisfied with explaining the 
distribution of species through soil and climate, but as 
the study of their appearance proceeded it was discovered 
that there were great gaps in the extension of many. And 
these gaps were often so great that scientific men were 
obliged to resort to explaining the same by maintaining 
that such species were created in places far apart. But 
since the doctrine of the origin of species by descent has 
been accepted, such anexplanation mustbe rejected. There 
remains, therefore, only two ways in which to explain 
these things. Either wind, animals, or sea-currents are 
capable of carrying the seed of plants at once across such 
large areas that the gaps in the extension can be explained 
by the means of transport at work at present, and there 
are even those who still believe that this is the case, In 
certain instances this explanation is indeed the only one 
possible, when, for instance, it concerns the flora and 
fauna of the oceanic islands which have never been con- 
nected with the great continents, and still have species 
more or less related to those of the mainland. But such 
a sudden migration is very improbable, and may even be 
dispensed with altogether, as we shall presently show, 
when it is necessary to explain such gaps in the extension 
of whole groups of species as those we have pointed out 
above in the flora of Norway. 
We haye, besides, another explanation of this problem, 
first advanced by Mr. Edward Forbes, who maintained, 
in common with most modern botanists, chat the climatic 
variations of the past are reflected in the fauna and flora 
of the present. He was, we believe, the first savant who 
demonstrated that the Glacial Age has left its distinct 
mark on the flora of the present day. Arctic species are 
found on mountains in temperate climates. During the 
Glacial Age these species grew in the plains at lower 
latitudes, but as the climate became milder they receded 
gradually to the far north and the high mountains. In 
the warm plains they had to give way to the new immi- 
grants, and this is the reason of our discovering hyper- 
borean plants on the mountains of Europe. 
lf now we were to apply this explanation to the scat- 
tered extension of the species in Norway, we must bear 
in mind that the distances here are smaller, although at 
times there are several degrees of latitude between the 
places where the same appear. We must, therefore, see 
if an acceptable explanation of the extension of the Nor- 
wegian flora can be made by means of geology, and if 
the same be supported by other circumstances. 
It is not long since, geologically speaking, that the 
Scandinavian peninsula was covered with an inland ice, 
stretching right out to sea, above which only solitary 
mountain-tops rose, like the “ nunataks ” in Greenland. It 
is evident that the majority of the present flora could not 
then exist in Norway ; but the present flora is older than 
the Glacial Age, which is conclusively proved by specimens 
from the same being found in coal strata older than that 
period. Thus yew, fir, and spruce, hazel, willow, &c., have 
been found in old peat-bogs of England and Switzerland, 
for instance, which are covered by the bottom moraine 
of the inland ice. The present Norwegian flora, there- 
