GREA T BRIT A IN. 255 



that the cycle is about to terminate. The same irregularity 

 of appearance has been observed in Norway, as regards 

 their winter herring fishery, and the theory most generally 

 accepted is that the fish have been at times compelled to go 

 further out to sea during the summer in search of their 

 food, and have been unable to return to the coast in time to 

 spawn, so have deposited it upon some of the large banks 

 in the middle of the North Sea. When the fish have not 

 been seen off the coast, large numbers of whales and sea- 

 birds, which live on herrings, have been observed off these 

 banks. It has also been remarked that when these fish 

 have reached the shore later than usual at the end of 

 January or commencement of February, it is commonly a 

 sign of their periodical disappearance. 



The following figures show, as far as I have been able to 

 ascertain, the presence or absence of herrings in Norway 

 and Sweden : 



Years. Norway. Sweden. 



1567-1589 . absent . . present 



1590-1643 . . . . absent 



1644-1650 . . present . . 



1651-1665 . . absent . . 



1666-1680 . . present 



1681-1691 . . . . absent 



1692-1746 . . present . . 



1747-1784 . . . . present 



1785-1808 . . absent . . 



1809-1835 . . present . . absent 



In 1835, in Norway, they commenced to go south, and in 

 1877 they reappeared in Sweden. 



The question arises whether, during the whole of these 

 long periods of absence, the fish remained off the coast, but 

 in the deep sea, while due to some unascertained influence 

 they did not rise to near the surface nor approach the shoal 



