210 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



herring are every year in largest cumbers in their accustomed places, 

 "there is no reason to suppose that the spring-herring fishery will come 

 to an end, although the fisheries may, on account of many accidental 

 circumstances, be more or less productive in the different years. 



Professor Sars's theory will become clearer to the reader by casting a 

 glance at the accompanying map.* This theory must be plausible in a 

 high degree, and no serious objections to it can be raised, as it seems to 

 explain the most characteristic phenomena of the Norwegian herring- 

 fisheries in a satisfactory manner. The criticism of its details we will 

 leave to those who have made, or are going to make, the herring-fishery 

 and the natural history of the herring the subject of special studies. Its 

 weak points (if they may be termed such) can easily be pointed out : 

 first of all, to use a simile, so many and large drafts are issued on the 

 unknown, the unproved, and the unprovable. It will be difficult to at- 

 tack Professor Sars in the rear by proving to him that the herring is not 

 found in those places which he assigns it during three-fourths of the 

 year, or that the former relations of wind, current, and weather in the 

 North Sea do not show any periodicity which corresponds with that of 

 the herring-fishery. But, on the other hand, it must be remembered 

 that no proof has been given that all this is not so. Another weak point 

 in Sars's theory is that it cannot easily be applied to herring-fisheries 

 outside of Norway. At least, one cannot read Mr. Sars's application of 

 his theory to the Bohuslen (Sweden) fisheries with entire satisfaction: 

 "At a time when the small crustaceans, on account of the peculiar cur- 

 rents of the ocean, have filled the North Sea and the Skagerak to an 

 unusual degree, it can easily be imagined that a portion of the great 

 mass of herrings coming originally from the uorthwest have got so far 

 into this part of the sea that, on the approach of the spawning-season, 

 by following the usual southeasterly direction, they have come toward 

 the coast of Bohuslen, where they have spawned, and later, in obedience 

 to the instinct common to all fish, have returned to the same coast where 

 they have spawned once, thus gradually forming a race of herrings pecu- 

 liar to the Skagerak, whose disappearance must at any rate in part be 

 ascribed to the less bountiful supply of small crustaceans in this part of 

 the sea." These possible weaknesses of the theory do not, however, as 

 Professor Sars very justly remarks, reduce it to a mere play of ideas, or 

 detract from its merits as a satisfactory explanation of some of the most 

 important and most obscure points of the whole question, but leave it 

 as a combination of phenomena according with well-known facts, which 

 may form the basis of further investigations, carried on with a fixed plan 

 and in a thoughtful manner. Let us hope that out of the fiery ordeal to 

 which future investigations will put it, it will only come out stronger ! 

 For the present we welcome it sincerely as an important step in advance. 



0. L. 



* The map referred to has not been reproduced. 



