4 H. MØLHOLM HANSEN 
According to Thoroddsen (1914) these features are of great im- 
portance in their bearing on life in the sea, both as regards its flora 
and fauna. We find, in fact, on the north and east coast, a flora 
and fauna of arctic character, whereas those of the south and west 
coasts are of temperate character. Up to the present, this has been 
confirmed by investigations on the flora of marine algæ, plankton, 
and the fish fauna, as well as deep sea and bottom fauna. The 
same conditions seem to be of no slight importance as regards life 
on land, as the present research inter alia will show. 
The temperature along the coast shows, according to Thorodd- 
sen, the following values: On the south and west, the mean surface 
temperature is 5—7° C., while to the north and east it is somewhat 
lower, 3—4° C. 
At the Vestmannaeyjar (South Iceland) the surface water during 
the coldest months (Decbr.—Febr.) shows a monthly average of abt. 
4°C., and in the hottest months (July—Aug.) abt. 11° C., the annual 
mean temperature being abt. 7° C. 
Stykkishölmur (W. Icel.) has for Febr.—March temperatures of 
0.3°—0.4° C. and July—Aug. 10.4°—10.6° C., with an annual mean 
temperature of 4.9° C. Grimsey (N. Icel.) a March temperature of 
0.7° C., August 7.4° C., with an annual mean of 3.8° C., and Papey 
(E. Icel.) has a Febr.—March temperature of 0.4°—0.5° C., Aug. — 
Sept. 6.6°—6.2° C. with a mean temperature for the year of 3.2° C. 
It will be seen from this that the temperature of the surface 
water decreases parallel with the volume of Gulf Stream water. 
From South Iceland west and northward round to East Iceland we 
have the following values for mean annual temperature: 6.9°—4.9°— 
3.8—3.2° C. East Iceland has the lowest mean temperature and 
the greatest volume of the Polar water; South Iceland the greatest 
volume of Gulf Stream water and the highest mean annual tempe- 
rature. | 
The temperature of the air is closely correlated to this (see 
Table 1), being, however, nearly always lower than the surface tem- 
perature of the sea water, the difference amounting on the average 
to a couple of degrees. We find, for instance for the temperature 
of the air, the following mean values: 5.1°—3.0°--1.5°—2.4° C. that 
is, following the coastline round from S-W-N-E. 
The greatest difference is apparent during the coldest months 
of the year, October to March, less in summer from April—Sep- 
