LJUXGMAN — SECULAR PERIODICITY OF HERRING FISHERIES. 503 



great herring fisheries, and their varying length and importance. It 

 not only explains the varying occurrence of the herrings during the 

 period and their final disappearance, but also their regular return ; and 

 it does this in a manner which offers far less difficulty than the older 

 explanations, not even excepting my own explanation of these phe- 

 nomena by changes in the cenobitic condition of the spawning-places 

 produced by the disproportionately large size of the schools of herrings. 

 The theory which I have advanced throws new light on the herring 

 fisheries and on the nature of the herring which at some future time may 

 be the subject of another treatise. 



