The Botany of Iceland - 01.12.1942, Síða 19

THE PTERIDOPHYTA AND SPERMATOPIIYTA OF ICELAND
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true mountain-ranges; to be noted are the mountain-chains extending
outward to the Reykjanes and the Snæfellsnes peninsulas. At the heads
of the fiords where the various valleys branch off into the interior of
the country there usually occur groups of mountains with crests, ridges
and peaks, often showing fantastic forms, while the edge of the
mountains along the fiords frequently resemble walls with bastions
and battlements.
Most of the hills occurring in Iceland are, in fact, sections or frag-
ments of originally continuous plateau-land split up by numerous
intersecting valleys, but more or less isolated mountains or mountain-
masses also rise above the lowland plains or above the great central
plateau. Apart from the higher mountain-domes covered with etemal
snow, the hills are usually clad with a more or less scattered and very
variable vegetation, at least in their lower parts; and even up to the
snow-line or the summit of the snow-free hill-tops higher plant-life may
be met with.
In many places the Icelandic table-land has its marginal parts cut
up into tongue-like sections, and these are usually traversed in all direc-
tions by clefts, and valleys formed by erosion. This intersected table-
land frequently extends to the sea, leaving no room for low-lying fore-
shores. Often wild mountains are met with, with narrow gullies through
which torrents force their way. And down the mountain slopes rush
numerous smaller rivers, while the larger rivers are as a rule hidden in
deep ravines excavated in the rock. At the mouth of the ravines the
river will usually deposit its load of gravel, sand, and clay in an
extensive cone of deposits. The inner highland is, generally speaking,
a rather monotonous plain with an undulating surface, consisting of
vast lava-fields or large gravel or stone deserts. The average height of
the interior is about 700 m, but above this level dome-shaped plateaus
up to 1400—2000 m s. m. rise in a row from the northwest to the
southeast. These domes are covered with glaciers, and separated from
each other by intervening broad valleys. From the glaciers descend
numerous tongues of ice (Skriðjökulls) which in melting provide the
water for the many rivers of great volume. This row of glaciers also
forms the water-shed between the rivcrs running through the northland
and southland respectively.
The north-western peninsula (Vestfirðir) is a small separate plateau-
land, almost cut off from the mainland by Breiðif jörður and Húnaflói;
the coast is deeply indcnted with fiords, and is bounded almost every-
where by steep mountain-sides often rising nearly vertically from the
The Botany of Iceland. Vol. IV. Part I.
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