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things that it was collected by one single kind of apparatus only, the ordinary commer- 

 cial trawl, and that it is unequally distributed over the whole North Sea and all periods 

 of the year. From the northernmost parts of the North Sea especially, there is relatively 

 but little material. And the material can just as little be taken to be representative of the 

 catches of the trawlers. For this it is also too small, and further, the steam trawlers 

 seek more definite fishing grounds whilst the catches of the research steamers are more 

 scattered. Just in this regard however the material has perhaps a special value. 



We see quite clearly, that a still larger and more uniformly collected material is re- 

 quired for a final judgment of the stock of fish on the large regions of the sea and 

 especially for framing any final decisions or proposals of practical significance. On the 

 other side we have been of the opinion, that such a great undertaking as the collection 

 of a^substantially larger material could not and should not be proceeded with, without 

 some such preliminary work as the one just ended. In this light the present material 

 has great value, both for the development of the methods and for the elucidation of cer- 

 tain main facts, which it seems to us are already quite obvious. 



In Damas' paper we also have numerous measurements, chiefly from the Norwegian 

 coast and the coastal waters. The work contains, further, thousands of age determinations 

 of the four gadoids mentioned, through which it gains a special importance of its own, 

 as it is the first time that so many direct determinations of the age of the gadoids have 

 been published. The determination of the age is based on the investigation of the fish 

 scales, which offer the practical advantage that the collection of the material and its 

 determination can be quickly carried out. With the help of these age determinations the 

 measurements and the statistical data obtain an increased value. In the section on the 

 cod the value and importance of the age determinations will be specially described. 



D'Arcy Thompson's report deals with the quantities of haddock and cod landed by 

 the Scottish steam trawlers. The main fishing grounds of these steamers lie in the north- 

 ernmost part of the North Sea. Similar material for the Southern North Sea is lacking; 

 only some preliminary information from Henking is available. Nevertheless D'Arcy 

 Thompson's paper is of the greatest importance for the whole of this report, as it throws 

 light upon essential points in the results obtained by means of other methods and gives 

 a broader basis to these results, just because the statistical data come from so large a 

 number of hauls. 



As a summary of these reports and referring to them for all details and the more 

 definite evidence, we may now discuss each of the four species separately. 



I. The Haddock 



Whilst the earliest bottom stages of the cod, coalfish and whiting are to be found 

 mainly in the littoral region of the coasts, the smallest stages of the haddock only occur 

 further out and in deeper water. The young bottom stages were found in great quan- 

 tities chiefly in the northern deeper part of the North Sea and in the Skager Rak. 



