General remarks. 
Prof. dr. HELLAND HANSEN’) has given an account of the hydro- 
graphical situation in the North Atlantic area cruised by the 
M/S Armauer Hansen in 1913. From HELLAND HANSEN'S paper it 
may easily be seen, that the hydrographic sections represent a 
typical picture of mixture of oceanic water from a southern and 
a northern origin. Areas of mixture are characterized by the 
occurrence of vortices, and one such was also reported between 
st. 5 and 7 in the said section. From the hydrographical con- 
ditions we may assume that the biological picture which can be 
drawn from the collections of plankton at the different stations 
is not homogeneous. To be brief there is a heterogeneous com- 
pany of organisms inhabiting these waters. In the samples, 
northern and southern forms are intermingled, and as the grea- 
test bulk of water is of Atlantic origin, most species are the 
same. From the cited paper we learn, that the water of the At- 
lantic current is thicker on the east than on the west side of the 
Rockall-plateau, and on the west side Guli-stream water was no- 
ticed at stations 5 and 14, where plankton also was collected. 
This circumstance is verified biologically by the occurrence of 
many southern forms at the stations above mentioned. 
On the other hand, there are several species of copepods 
in the precsding list which are regarded as arctic, the presence 
of which in these waters must be due to transport by currents 
from the North. The hydrographers have also shown that such 
currents really exist. In a paper from 1912, F. NANSEN?) has 
rendered a review of the hydrographical conditions on the rid- 
1} A ASO), på 61. 
2) B. A.M. 
