THE SALMON FAMILY 47 



These fish during the early part of their lives are 

 almost identical in appearance, and for the first year or 

 two possess bars across the body known as parr marks. 

 These parr marks probably persisted throughout life in 

 the primitive trout ; even now they are permanently 

 present on the mature trout of the Scottish burn, where 

 food is scarce. Their spawning habits also point to a 

 common freshwater ancestry, for salmon, sea trout, and 

 brown trout that have acquired the habit of going to 

 sea return to fresh water to spawn. Neither will the 

 eggs of these fish live in sea-water. 



As illustrations of the possibilities of variation in the 

 brown trout, let us consider the Loch Leven at home, 

 and the brown trout as he now appears in Tasmania and 

 New Zealand. 



The Loch Leven trout, with its silvery sides and black 

 cross marks, turned into a southern trout stream, in two 

 or three months changes his colour and markings, and 

 is difficult to distinguish from the common brown trout. 



Brown trout introduced into Tasmania and New 

 Zealand at first maintained the characteristics of our 

 trout at home. Now these fish weigh twenty to thirty 

 pounds, migrate to sea and return to fresh water to 

 spawn, and in appearance are as silvery as a salmon. 

 The young, however, of this altered brown trout during 

 the first year of life cannot be distinguished from yearling 

 brown trout as seen at home. 



In view of the above facts, let us look at the life 

 history of the brown trout as a type, and then consider 



