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years, distinction has been made (in Norway especially by G. O. Sars) between spawning 
migration and migration in search of food. Sars places in the latter category the move- 
ment of the loddefisk towards the Finmark coast, in pursuit of the capelan, as also 
the sojourn of the fat herring in North Coast waters, where abundance of plankton is 
to be found. Sailing from Bergen in summer towards the Shetlands, one encounters 
first, on the Revkant, the Norwegian herring which have spawned during the spring, 
and develope their genital and fat containing organs again in the course of summer and 
autumn. Farther on, one meets the Shetland herring, moving in to their spawning 
grounds. It is interesting to compare, at this time of year, the contents of the stomach 
in these two races of herrmg and the pelagic organisms in those parts of the sea in which 
they move. I had occasion to make some investigations of this nature in 1912, and 
will here mention some of the results obtained, on the basis of the samples taken, which 
were determined by PAUL BJERKAN. 
In the Norwegian Channel, vertical hauls from bottom to surface, (e. g. from 360 
—0m) with a 1m. silk net, showed, besides small crustaceans, Copepoda (Calanus, Eu- 
chaeta norvegica, Metridia) also larger crustaceans, Ephausida (Meganyctiphanes nor- 
vegicus, Thysanoessa longicaudata). Vertical hauls from lesser depths (75—0 m) showed 
only Copepoda, no Ephausida, which latter must therefore be presumed to be restricted 
to the deeper water layers. Closer in, on the banks, only larvae of Ephausida were 
found, no full-grown specimens. The crustaceans here consisted almost exclusively of 
Copepoda. 
On examining the contents of stomach of the herring, it was at once noticed that 
the Shetland fish contained far less than those from the Revkant. In samples of 50 
Shetland herring, the contents of stomach varied between 20—60 cubic cm., whereas 
50 of the Revkant fish exhibited a total of 205 cubic cm., consisting of 338 Meganyvti- 
phanes norvegicus (of more or less equal size), and 8 Rhoda (Boreophausia) raschu, (of 
different sizes). Some of the stomachs being empty, this gives an average of more than 
7 crustaceans per fish. 
Investigations of this nature should furnish very valuable results, if extended to 
various waters, and carried out at different times of the year. 
Similar investigations have occasionally been made as to the contents of stomach 
of cod and coalfish. In the Finmark waters, cod taken in the spring (April and May) often 
contain large quantities of capelan; I have found as many as twenty or more in the stomach 
of a single fish, while great numbers of Ephausida may be found in the stomach of the 
coalfish. Such mvestigations would go far to explain the migrations of the fish outside 
the spawning time. Particular interest in this respect attaches to such regions as the 
Bottlenose Ground, the Barents Sea, and the outer limits of the Norwegian Sea, where 
Ephausida, cuttlefish, and other organisms are found in abundance in the summer. 
Variations in the quality of the cod. 
In the cod, the fatty deposit is found partly embedded in the flesh, (between the 
muscles) and partly in the liver, where it is found in great quantities. This organ, in 
the case of the cod, discharges the important function of storing up a reserve of fat which 
is consumed as the needs of the system demand. The state of the liver is therefore subject 
to very great variation. Among the mature cod, or “skrei” we may find individuals 
