The Botany of Iceland - 01.12.1912, Page 67

MARINE ALGAL VEGETATION
53
Table 1. The Distribution of the Species along the coast (continued).
E. Icel. N. Icel. NW.Icel. SW.Icel. S. Icel.
Cyanophyceæ.
b2 Pleurocapsa amethystea c + + 4- + +
I) Plectonema norvegicum (c) +
E Phormidium autuinnale (c) + ..
C Spirulina subsalsa (c) + +
C Calothrix scopulorum (c) + +
C Rivularia atra (c) +
From Iceland (31, 14 and 57) tliere are published 76 species of
red algæ, 67 species of brown, 51 of green and 6 af blue-green —
200 species in all. All of these, of course, are not equally common
along the coast, and their habitats, as far as these are known, in
the hve districts into which the coast is divided, are given in the
above table. That table shows that comparativelv few species occur
in all the coastal districts (in tlie table, such are imiicated by the
letter c placed after the name of the species). In all parts of the
coast are found 15 species (20 %) of red algæ, 18 species (26.8 %)
of brown, 10 species (19.6%) of green and 1 species (16.6%) of
blue-green. Thus, of the 200 species there are 44 species (22 %)
which are common to all the coastal districts.
If we take into consideration the fact that tlie great stretch of
coast round tbe wbole of Iceland is as yet far from accurately investi-
gated, we may expect, after future investigations, not only that several
niore species will be fonnd, but also that thc distribution of the
species in the different parts of the coasl will prove to differ from
what is at present stated to be the case. Therefore, in the above
list of the distribution of the species along the coast I liave placed
a (c) after the name of those species which, as I surmise, are pro-
bably to be found in all parts of the coast. I base tbis supposition
partly on the position of the habitats already known along the
coast, and partly on the occurrence of the species in the adjacent
floral districts, e. g. the Færöes and Greenland.
The mark (c) is subjoined to 14 species of red algæ, 29 species
of brown, 32 species of green and to 5 species of blue-green. On
adding to this the above-mentioned species which liave the letter c
subjoined we get 29 species (38 %) of red algæ, 47 species (70 %)
of brown, 42 species (82 %) of green and 6 species (100 %) of blue-
green. Thus, of the 200 species 124 prove to be common to all parts