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for the first time.”) The cod on the shore often shed already while they 
are rather small — 9 inches, says Dannevig. But the North Sea cod is 
considerably longer before it sheds, c. 20—22 inches. If I am not mis- 
taken, G. 0. Sars, in Norway, has also already called the attention to this 
phenomenon, and explained it in a similar way as Dannevig, as an indica- 
tion of the existence of special fjord-races. I myself can state that the cod 
often sheds in our Belts, when it is 14 inches long, and perhaps still smaller. 
But to state this fact is a very different thing from declaring these codlings 
to be a true race; to do so, it is necessary to have proofs. Such, however, 
I do not know at all. Suppose a man takes a sack of quite homogeneous 
grain, of wheat, barley, or any sort of corn, and sows it in different places, 
part in fertile soil, part in poor soil. Though the offspring here are brothers 
and sisters, consequently of the same race, the corn turns out very differently 
in the different places; but we are not entitled to call the thin, short corn 
in the poor fields another race than the fme corn in the fertile fields. It is 
only external conditions which have produced individual variations, distri- 
buted in groups, "external races”, which disappear when the grain is sown 
again in another soil. Someting more is wanted to form a true "internal 
race”; it must not so. easily loose its racial characters by transplantation. 
But I shall enter no further into this question of races which is of such a 
great importance in nature. I only wanted to point out that the cod 
in the fjords and shore-waters, although they do not in everything agree 
with the cod in the more open seas, very well may be their direet offspring, 
and the children of the latter, nay, perhaps themselves become North Sea cod 
when they grow older. For these differences, as we have seen, may have 
been produced only by change of dwelling-place (the colour), and therefore 
be very variable, and all of them may perhaps quite disappear when the 
fish grow older. At any rate, before we can believe in particular fjord- 
races, we must be able to point out their fry and to show their whole 
development in the fjords — and this is just what we cannot do. If such races 
really did exist, we must also be able to point out certain characters which 
were independent of age and dwelling-place; but all such attempts, since 
the time of Linné, have failed. — In order to check the results of these 
biological investigations, in some measure, I tried to find out, whether 
any difference could be pointed out in the number of rays in the fins of 
the cod in the Cattegat and that in the North Sea. The number of 
£) Different colours of the spawn of the cod, to which Dannevig refers as a race- 
character, are, in Hjort's opinion, of very little consequence, as the colour is dependent 
on the various contents of fat in the eggs or the milt, and these depend very much on 
the food which the fish gets, both as to quantity and quality. The fat contained in the 
food, according to the latest physiological views, goes directly into the organism without 
changing its chemical combination. Moreover, the colour of the spawn does not keep in 
the hatched fry, so that there is scarcely any reason to attach any importance to this 
whole matter. 
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