ON TEOUT. 



71 



is dependent on such fish as chance to enter it from the Luostijok during 

 a flood. 



The seven fish which I have obtained from this lake have been used in 

 drawing up Fig. 30, in which the growth curves for each of the trout are 

 shown. The unbroken lines of the curves denote the period of slow growth, 

 and the dotted lines show when growth was rapid. 



The values from the Luostijok are, according to the comparative 

 statement on page 69, as follows : 



Calculated Average Length in cm. at Formation of each Winter-band. 



Now if we consider the curves in Fig. 30 in relation to these figures, 

 it will at once be seen that each single fish, at the period of transition from 

 slow to rapid growth, was of a size resembling the corresponding sizes 

 from the Luostijok, and that the average values for the unbroken parts of 

 the curves agree very closely with the average values from that river. On 

 the other hand, each single fish in the lake, after change of growth, has 

 developed much more rapidly than the fish which remained in the 

 Luostijok. 



There is not much doubt, then, that these trout have spent their youth 

 in the Luostijok and entered the Gjeddevand during a flood, and have found 

 there quite different conditions of food from what they were accustomed to 

 in the river. Whatever their origin may have been, the fact .remains that 

 their growth history is clear evidence that these inland trout possess the 

 same faculty of developing great changes in their rate of growth, as we 

 found to be the case with salmon, sea trout, and Mj0sen trout. 



They also furnish clear evidence as to the difference which may occur 

 in growth even in closely adjacent localities, since the land dividing 

 Gjeddevand from the Luostijok ver is not more than about 10 metres 

 broad. 



