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but to which they were only carried from elsewhere is also interesting. We may take 

 a fjord, Stor Fjord, east of the Romsdal Bank. Almost no eggs are spawned here, but 

 shortly after the cod had spawned outside on the Romsdal Bank, cod larvae as well 

 as eggs appeared in the fjord, in numbers calculated to be 252 and 106 

 millions per square kilometer. 



We meet with greater difficulties in trying to give a picture of the quantitative oc- 

 currence of the older pelagic stages and young fishes, among other reasons because they 

 are more difficult to take and because they occur distributed over larger areas than the 

 eggs and earliest larval stages. On account of this dispersion and perhaps also on ac- 

 count of the death-rate, it can be understood that our catches will never be so rich in 

 larvae as in eggs. It was possible, nevertheless, to obtain the young gadoids in thousands 

 at least in a single haul with the various young-fish nets. Schmidt reports, that in a 

 single haul lasting 30 minutes with Petersen's young fish trawl on June 27th at West 

 Iceland he obtained about 7000 young fishes of 22 different species. Amongst these the 

 gadoids were in the majority. In the North Sea also many hauls, e. g. of young whiting, 

 were made, in which the numbers amounted to thousands in each haul. Further, on 

 the coasts of Norway and Iceland thousands of the very earliest stages, which collect 

 together in the littoral region (especially of coalfish and cod), were taken near to land in 

 a single haul with the seine. It is evident, however, that these rich hauls cannot give us 

 to the same extent as the egg samples a quantitative picture of the number of these 

 stages in any definite area. As soon as the young fish are capable of active movements, 

 they seem to become much more unevenly distributed; the small fish come together in 

 shoals and undertake active wanderings. The determination of their quantitative occur- 

 rence within any fairly large area is then connected with the greatest difficulties. 



We possess something, however, which enables us to a great extent to understand 

 better the question of natural increase in the earliest stages, namely, our observations on 

 the great changes which have appeared in the numbers from year to year. 



Some prominent examples of this may be mentioned. 



The young of the whiting were investigated in the North Sea in the 

 years 1904 — 1906, as well as in other years. In June and July of 1904 enormous quan- 

 tities of the pelagic whiting fry occurred on the surface in the Northern North Sea. In 

 1905 the investigations were repeated at the same place and at the same time of year, 

 but the catches were much smaller, yielding on an average only V4th of the catch of the 

 previous year. 



In 1906 large quantities were again found in the central part of the North Sea on 

 the Great and Little Fisher Banks. 



In the Norwegian Sea extensive investigation cruises were undertaken throughout 

 several years in order to chart out the boundaries of the occurrence of the pelagic young 

 gadoids in summer. It appeared from these, that the region of distribution was quite 

 different in the different years. 



In the North Sea, particularly the southern half, the English and German research 

 steamers investigated the earliest year-groups of the haddock. The working out of the 

 material showed amongst other things that the different year-groups were quite differently 

 represented in the hauls. The 1903 group for example occurred but sparingly, the 1904 

 group on the other hand in great numbers. Very similar conditions were displayed by 



