— 124 — K ’ Pa 
zones themselves shows the nature of the growth. By examining the scales of fish taken 
at different times of the year and in different waters, the relation of the growth to the 
external natural conditions associated with different seasons and localities may be ascer- 
tained. 
Acting on these principles, Damas made a great number of observations in different 
waters as to the age and growth of various species of cod, discovering considerable dis- 
similarity in the latter respect. In the North Sea, the growth of the cod was found to 
be rapid and even, while the skrei of the Lofoten banks exhibited a slower growth, in 
which a very distinct periodicity was noticeable. Between these, various intermediate 
classes are found, as also between the cod having their habitat near the open sea, and 
those of the fiords. 
The influence of the season of year upon the growth was found to differ greatly 
in different waters. In the Skagerak, haddock with ovaries in a mature state have 
been taken in July (K. Dahl), the edges of the scales showing “winter growth”. In the 
Barents Sea, outside the mouth of the white Sea, the “summer growth” had not begun 
in August. 
Examples of different growth in different waters. 
Fig. 83 shows scales of four cod, all of about the same size, 27—31 cm., from different 
parts of the Norwegian coastal waters, F. from Fredrikstad, (Christiania Fiord), B. 
from Bergen, H. Helgeland (Nordland) and V. Varde (Finmarken). The scales of 
the cod from the southern waters show only one winter ring inside the edge, those of 
the northern fish having two. If we calculate, in the manner employed in the case of 
the herring, the size of these fish at the different periods of growth, we obtain the fol- 
lowing results. 
Growth of certain young cod from 4 places on the coast of Norway: 
Place Length ist year’s growth 2nd year’s growth 3rd year’s growth 
Fredriksstad. F. ..... 27 cm. 16.4 cm. 10.6 cm. 
BEEN IB; 4406000000 29) — 14.3 — 14.7 — Lay 
Helgeland. H.-:..... 29 — 14.7 — ‘ 9.5 — 4.8 cm. 
Varde.)V creckiacment. 31 — 8.3 — 10.5 — 12.2 — 
Both the first and second year’s growth exhibit great variation; it is particularly 
noticeable that the growth in these years is very slight in the case of the northernmost 
specimen, from Vardo. Since the scales can show so great variation, it is interesting 
to more closely consider the question as to whether scale investigations, also in the case 
of the cod, can give as reliable results as those obtained by Lua in the case of the herring, 
and if so, to employ the method for further investigation into the growth of the cod 
in different waters. Such investigations have already been commenced by Oscar SunD, 
who has furnished me with the following particulars as to the results hitherto obtained. 
Sund’s methodical investigations as the utility of the scales in the study of growth. 
“The scale covering of the cod and coalfish is not quite so regular as in the case of 
the clupeidae, which exhibit exactly one cross row of scales to each myomer. In the 
