62 THE AGE AND GROWTH OF SALMON AND TROUT. 



is concerned, is obvious enough ; whether, however, the spawning females 

 take part in this migration at a later period of their existence, or whether 

 their lives terminate more quickly here than in land-locked lakes, where the 

 fish attain considerably higher ages, is not easy to decide. 



This much, however, we can be positive about, that these streams to 

 which sea trout have access, contain a stock, which mainly consists of young 

 fish, and it is very probable that the whole of this stock of young fish 

 contribute towards the recruiting of the stock of sea trout. This is, too, 

 the most likely reason why we so seldom find older fish in these waters. 



With regard to rate of growth the conditions vary a good deal. I will 

 set down here once more in tabular form the empirically found average 

 sizes of trout in the waters referred to. They are taken from the tables 

 already mentioned (Tables XXI. XXVI.). 



The number of observations on which each average is based are added in brackets. 



B. Instances of Trout from Waters to which Sea Trout have no Access. 



1. LAKE Mj0SBN TROUT. 



We will first consider examples of the large trout which live in Lake 

 Mjosen, and which in summer and autumn ascend the river Laagen to 

 spawn. They are fished for in that stream under the name of " Hunner 

 Trout," a name derived from the old fishery at the farm of Hunner. 



Herr Sogaard, of Lillehammer, has been kind enough to allow one of 

 his employees to collect samples of scales from the trout which passed 

 through his shop from the end of June to the beginning of September. 

 The collection represents 171 fish, all taken in the Laagen above 

 Lillehammer. 



In Tables XXVII. and XXVllB. I have put down the results of my 

 analysis in the same way as I did in the tables for salmon previously 

 described. Table XXVII. contains an analysis of age in relation to length, 

 and Table XXVIIs. deals with age in relation to weight. 



The tables are arranged in such a way that the age of the fish, previous 

 to and subsequent to migration is shown, but the statistics of size are given 

 subsequent only to migration. 



