CURREN T-LELERA TURE. 
BOOK REVIEWS. 
The algal vegetation of the Faeréese coasts. 
BORGESEN’s extremely interesting account of the algal associations on the 
coasts of the Faerée Islands,‘ is one of the most important contributions to the 
cS eran ll «Sey 
ecological side of marine botany. The work is a description of conspicuous algal 
associations along a varied rocky coast line, particularly favorable to algal vege- 
tation, and is illustrated by more than thirty very excellent plates and figures 
from photographs. The factors affecting the algal vegetation are discussed; 
such as temperature and salinity of the water, tides and currents, wave action, 
temperature and humidity of the air, and light. The littoral and sublittoral 
floras are described, both for exposed and sheltered coasts, and also the floras of 
tide-pools and caves. A great many algal associations and formations may be 
clearly recognized in the Faerdes, some of them very conspicuous, as the Chloro- 
phyceae formation, the Porphyra association, Fucaceae formations, Laminariaceae 
formation, and Alaria association. A particularly interesting chart plots the 
position of these associations in their position above and below the mean sea level. 
It is extremely interesting to note that the cave flora is composed of forms of 
the sublittoral flora, which in the dim light are able to grow near the surface, or 
they are types which have the habit of growing in shaded situations outside. 
Littoral forms which grow in the brightest light are only found near the entrance 
of the caves. On entering a cave a condensed picture is obtained of the vertical 
: distribution of algae from above downward. The forms in the deepest shadows 
f are all red algae and some of them species which are usually found at great depths 
in the open sea. It is clear that light is the most important factor affecting the 
position of algal associations along a coast. 
There is a detailed comparison of the algal flora of the Faerée Islands with 
neighboring countries, Scotland, the Orkney and Shetland Islands, Norway, and 
Iceland, preliminary to a discussion of its origin. The flora had its origin from 
a mixture of Atlantic and Arctic species, which wandered northward with the 
retreat of the ice. Some of the arctic forms remained, adjusting themselves to 
the warmer waters, but there are many peculiarities of the algal flora which 
demand special explanations. BORGESEN does not believe that there were post- 
glacial bridges of land which made possible the migration of forms, but holds 
that factors now operative might have brought to the islands many algae from 
neighboring countries. 
* BORGESEN, F., The pee peta of Faerdese coasts. Im 
834. pls. 13-24. Meads en: . Thiele. 1905. [Reprinted ible ‘Rtens a 
the Faerdes. See Bor. GAZETTE ty 392. 1903-] 
1906] | 71 
