IV. Alterations and Improvements on Otter-seines 
for Zoological Purposes. 
In Report VIN of the Danish Biological Station, 1898, I gave a de- 
scription and a picture of an otter-seine, of which I had made use for 
catching the more quickly swimming animals, such as larger crustacea, 
smaller fishes, etc. This seine has afterwards been employed by many 
vessels, larger as well as smaller ones, and has nearly always worked satis- 
factorily. Of course, the working of it requires more practice than the 
manoeuvering of an ordinary dredge, as it is next to impossible that the 
latter can run foul when it is let down. That the seine, however, catches 
well, is proved by the fact, among others, that it is now used in Norway 
for the fishing of deep-sea prawns (Pandalus borealis). (See, as to this ques- 
tion, "Dr. Johan Hjort's essay). In Norway it is called "Ræketravl”, and 
is employed by common sailing-boats on 60—70 fathoms of water. Åccord- 
ing to statement, they fish for 1—200,000 Kroner a year with this otter- 
seine, on the southern shores of Norway. No doubt, it can fish then. But 
new hands at it, seem to have certain difficulties to overcome in the use 
of it: it sticks in too soft a bottom, it does not reach the bottom at all, it 
runs foul when it is let down, etc. 
I have, since 1898, made use of otter-seines to a very great extent; and 
I have succeeded in making various improvements on them, both as to the 
construction and as to the treatment of the apparatus. I shall here give 
information about these improvements, hoping that they may be of use to 
other investigators. For there are not a few people already who employ 
this seine. I have delivered specimens of it to Norway, Germany, Russia, 
Sweden, and Finland; in America they also want to make use of it. More- 
over, there are others who have delivered these seines to people abroad, I 
do not know how many, and perhaps people in other countries have tried 
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