194 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



although it has never become general, has been fully described in the 

 well-known works of Kroyer and Axel BoecTc. 



Andermii's migration-theory, which finds adherents to this very day, 

 has, in course of time, undergone various changes. Thus some suppose 

 that the herrings go into southern waters for the sake of ^propagating, 

 and then return with their young to the Polar Sea, which offers an 

 abundance of food [Pennant and others), because the herrings were seen 

 to come near the coast full of roe or milt and leave it empty ; and be- 

 cause Anderson'' s explanation of this fact seemed insufficient, one began 

 \(\ think of analogous facts in the life of birds and other migratory ani- 

 mals, or was forced to the opinion that there were inconsiderable changes 

 in the herrings' visits to the coast in the direction of their journey, &c. 



41. Andersoiis migration-theory was subjected to a thorough and anni- 

 hilating criticism by the distinguished ichthyologist Block, whose opinion 

 has been shared by Koel de la Moriniere, Lacepede, and Qiiensel. With 

 more originality MaeCulloch has also followed Blocli's opinion, and has 

 ■directed attention to the impossibility of m^aikiug Anderson^ theory agree 

 with the evident irregularities in the course of the herrings. Some 

 years before J/flcCi<WocA, Couch had opposed the migration-theory and had 

 described the character of the herring as a "local fish" on the coast of 

 Cornwall. >S'. Nilsson has with great emphasis pronounced himself in 

 opposition to the theory of a central school of herrings near the Pole, 

 and has specially mentioned the physical impossibility of the young her- 

 rings developing in the great deep of the Polar Sea ; he has also op- 

 posed the opinion that every coast should have its special race of her- 

 rings distinguished by outward marks and a separate spawning-season, 

 being, consequently, more local and littoral in its character.^' Professor 

 Nilsson, therefore, not only opposed the theory of a central race of her- 

 rings near the Xorth Pole, but of such a central race altogether. The 

 dispute caused by Professor Nilsson''s writings on the regulation of the 

 Bohusliin herring-fisheries caused the Eev. 0. Lundhecl', pastor of the 

 chiu-ch at Kladesholmen, to advance the theory of a central race of her- 

 rings probably living in the North Sea, to which we owed the great her- 

 ring-fisheries, and from which, in course of time, the smaller races of 

 coast-herrings had separated, a theory which might possibly be harmo- 

 nized with the views advanced in BlocKs criticism of Andersoii's theories,^* 

 but which is in direct opposition to the facts and opinions given by Pro- 

 fessor KilssoH. Lundhecys hypothesis found no adherents, and seems to 



^3 Professor KiJason weut so far in his zeal to give to every coast its special local race 

 ■of herrings, as to entirely deny the possibility of two or more different races occurring 

 "on one and the same coast and under exactly the same natural conditions." This 

 one-sided and doubtless erroneous opinion has recently found an adherent in Prof. G 

 O. Sars. 



^Bloch believes that the time of spawning dex^ends on age and temperature, and 

 from this opinion it may easily be deduced that the herrings which spawn in the North 

 Sea during autumn, and which are actually, somewhat smaller than the common her- 

 rings, are only the young of the Norwegian spring-herrings. 



