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spawning by counting the number of the newly spawned eggs, and dealt with the question 

 of the death-rate amongst the earliest stages during their further development, all for the 

 purpose of elucidating the relation between the stock of older fish and the natural increase 

 in new individuals. 



The investigations we are discussing here are far from being able to solve so great 

 a problem. To count the newly spawned eggs on all the different spawning places would 

 require an organisation of vessels, workers and means far greater than anything that was 

 at the disposal of the Committee in this way. The practical difficulties presented by nature 

 itself are however also so great, that no one would think of attempting the solution of a 

 task of this kind in undertaking such an investigation of the waters, as we have done, 

 for the first time. Difficulties such as, that the eggs are not spawned simultaneously 

 within the whole spawning region of the species and that the newly spawned eggs do 

 not remain at the geographical point where they came into the world, make the matter 

 still more complicated. It will seem natural, therefore, that the first endeavour was above 

 all things to ascertain the spawning places themselves from a purely geographical stand- 

 point. We had first to learn where the eggs mainly occur, before we could ever think 

 of organising a purely quantitative investigation, and this first geographical orientation was 

 in itself a sufficiently great aim for the first investigations. At the same time, however, 

 the Committee endeavoured at some chosen points to collect material which might be 

 suited to give the first picture of the number of newly spawned eggs at various parts 

 ot the spawning places. This material was obtained in various ways, partly by horizontal 

 partly by vertical hauls, and the number of eggs determined by counting. We may 

 give some examples of the results of these experiments. In the spawning time of the 

 cod in March 1906 on the spawning places of the Romsdal Bank, when a small silk net 

 of one meter in diameter was towed for five minutes slowly through the surface water, so 

 that the net to a certain extent skimmed the surface where most eggs were, the average 

 catch of such a haul could amount to 6o,OCX) cod eggs. If we picture how small the 

 part of the surface skimmed in this way is in comparison with the extent of the whole 

 bank, we see that the number of cod eggs spawned must be enormous. 



The occurrence of eggs on the northernmost North Sea slope, the so-called 

 "Tampen",. is perhaps even richer. On March 7th 1905 the "Poseidon" found here at 

 61° 13' N. and 0° 35' W. 456 coalfish larvae and ca. 450 coalfish eggs per square meter. 

 If we assume a uniform distribution of the eggs and larvae , this result would be the 

 enormous number of 456 million larvae and 450 million eggs per square 

 kilometer of surface. 



The "Michael Sars" made some investigations at the same place in April 1906. 

 It may be accepted that a considerable part of the eggs and larvae had already by 

 this time been carried away by the currents; nevertheless, it was calculated that apart 

 from the eggs at least 5CX3 billions of coalfish larvae were present on an area which lies 

 from west to east between the 1° and 2"" E. L. and between 61° and 62° N. L. 



An example of the numbers occurring at a place where the eggs were not spawned 



