KNUT DAHL. 



18 cm. Its occurrence in the table is caused by the fishing 

 also being carried on a little up the river. Consequently the 

 smaller fishes, which next spring would represent the youngest 

 group of emigrants, were also caught. 



Also in October the fishes which constitute the smallest 

 emigrating group of spring, invade the Gula. This is shown in 

 table VII, second last column. 



In my opinion, similar facts will be found in most rivers, 

 although I am inclined to believe that larger or smaller excep- 

 tions and variations may occur especially respecting the dates 

 of emigration and return. It seems very probable that the cli- 

 matic variations in this respect would assert themselves, and that 

 some difference would be noticeable as to southern and northern 

 latitudes in our vast country. 



That such difference, however, cannot be great, is clearly 

 shown by table VII, last column, which represents trout caught 

 in the Mandal river, October 25, 1901. 



There is no doubt, that this autumnal immigration of trout 

 as regards most large rivers, is a general phenomenon. Reports 

 to this effect, are present from many different parts of the 

 country, especially the surroundings of the lower parts of the 

 larger rivers, 



These reports are also interesting on account of the fact, 

 that these masses of trout which appear in the river mouths in 

 autumn, have very often been considered as young salmon. At 

 this time of the year, having spent the summer in the sea 

 among the herring fiy, they are really very fat, shiny and silver- 

 coloured; however, as described in Chapter II, they are easily 

 distinguished from salmon. These immigrating trout are in 

 most places in this country named „blankøre", „høstblege", 

 „biege", „lakseyngel" a. s. f. When leaving the river in spring, 

 the people around the Orkla and the Gula, and also many other 

 rivers, call them „is-fisk" (icefish) evidently because they are 

 caught when the ice is breaking up. As I have mentioned they 



