— 197 — 
tors in the same object (i. e. the same individuals). The greatest value therefore attaches 
to the testimony afforded by the similarity of the curves here in question. We see, that 
the so-called quality of the fish is mainly an expression of their age and growth, of the relative 
proportion in which the different age classes appear in the stock, and of the previous history 
of the stock itself; not in the first instance an indication of any momentary condition of the 
fish as regards nourishment, or of the state of the water in which they move. 
These results thus confirm and support, in a very high degree, the conclusions arrived 
at in the previous chapter; they show, moreover, the far-reaching effect upon the stock 
oceasioned by the varying occurrence of year classes consisting of large fish or small, 
with corresponding high or low value as regards the quantity of liver. 
The importance of the conclusions which I have here drawn from my own investig- 
ations will justify a closer consideration of some of the most important points, 
1880 5 1890 5) 1900 5 1910 
Fig. 123. 1. Average weight of Lofoten skrei. 2. Amount of liver in Lofoten skrei. 
3. Amount of roe in Lofoten skrei. 
and this may especially be necessary, as in the practical industry, many people 
have long been accustomed to attribute all fluctuations in what is called “quality” 
to transitory conditions. Moreover, certain remarkable facts have been observed in 
some recent years, especially in 1903, when the quantity of liver was perhaps less than 
ever before observed. In this year, the commencement of the skrei fishing season was 
accompanied by a number of peculiar phenomena, such as the immigration into Nor- 
wegian coastal waters of Arctic animals such as the beluga, and the Greenland seal 
(Phoca groenlandica), all of which combined to give the impression that a general 
dislocation of marine conditions was taking place. 
Comparison of the quantity of liver in the*first and last week of the skrei 
fishery. 
We have seen in the foregoing, that the changes which take place in the quality 
of the skrei from the time of their arrival on the banks to the conclusion of the spawning 
embrace, apparently, a very great proportion of the possible variations for the single year. 
