SALT-WATER FISHERIES OF NORWAY. 703 



near the "Storegg"; and daring our last expedition tlie same peculiar 

 currents were, to some extent at least, also observed near the "Lofotegg." 

 It is evident that the "herring-food" and with it the herring-schools 

 will ofteher gather here than in most other parts of the sea, and as neither 

 the one nor the other is strictly bound to the surface, but from various 

 causes often go deeper, the fish of prey living near the barrier have ample 

 opportunity to mingle in this game. 



Although the bottom codfish or algse codfish living nearest the coast, 

 which are in reality nothing but younger codfish, are not very fastidious 

 in the selection of their Ibod, there is every reason to suppose that the 

 full-grown bank codfish, or codfish proper, found near our coasts make 

 the herring, if not their exclusive, at any rate their chief food. If the 

 Northern Ocean did not harbor these large masses of herrings, there 

 would not be sufficient food for the enormous number of codfish which 

 in winter come to the coast to spawn, and which during that season form 

 the most important object of our fisheries. Here as everywhere in nature- 

 there is a close connection between cause and effect, which from a practi- 

 cal point of view we must explain and follow up to its last consequences 

 in order to get a clear idea of all those conditions which have an iufiueuce 

 on our fisheries. ' 



There is, as I said, every reason to suppose that our wealth of codfish 

 and similar fish of prey is chiefly dependent on the herrings in the outer 

 waters. And the herring again is dependent on the "herring-food" 

 found in the open sea. Without its great wealth of "herring food" the 

 Northern Ocean could not support the large masses of herrings, and 

 theseagain support the codfish found in our coast- waters. The "herring- 

 food" is, like the codfish and the herring, an organism which cannot 

 possibly live on nothing, but which in order to make its appearance in 

 such enormous masses must find a sufficient quantity of food in the sea. 

 But what constitutes its food? We have here reached the last link in 

 the chain of evidence, a link which is of the greatest importance, as all 

 the others depend on it. During our last expedition we had an oj^por- 

 tunity to make observations with regard to this important point. 



I have already mentioned in the partial report on the zoological re- 

 sults of our last expedition, that in the sea near Jan-Mayen, and espe- 

 cially where the low temperature of the water showed that it was mixed 

 with ice-water, we found enormous masses of a peculiar organic matter, 

 a kind of yellowisli-browu slime, which colored the sea- water for miles. 

 Accurate microscopic observations proved it to be a shapeless, indiffer- 

 ent, but living protoplasm. Farther south, on the height of the Vigten 

 Islands, we found a similar sea-slime, differing, however, from the former 

 by its consisting of formed microscopic organisms, chiefly a peculiar 

 kind of diatom. In my zoological report I have directed attention to 

 the great scientific interest attaching to the slime observed near Jan- 

 Mayen. From a more practical standpoint both kinds will be of equal 

 interest. We have here possibly two different links in our chain of 



