290 How to obtain it. 



little fish lose their trout-like appearance, including the bars, or 

 " finger marks," and that they become bright and silvery. They 

 are then called smolts, and are generally supposed to have got a 

 fresh set of scales, but this is not so. Their shining appearance 

 is caused, not by new scales, but by a silvery pigment secreted 

 on the undersides of the scales. This same silvery appearance 

 also affects the gill covers or opercles, which are not possessed of 

 scales. 



An interesting experiment was tried some years ago. A 

 number of salmon " parr " were taken from the river, and placed 

 in a fresh water aquarium tank. In due course about half of them 

 assumed the smolt stage, but the others did not. Sea water was 

 then added until the other was displaced, and, on the water 

 , f becoming salt as the sea itself, a very interesting result occurred. It 

 has been asserted that "parrs," as such, will not live in salt water- 

 These not only lived, but very soon assumed the smolt stage. 

 We know that salmon " parrs " and smolts when in a river feed 

 voraciously, for they will take nearly any bait. They are found 

 gorged with shellfish, larvae of insects, etc. So voracious are they 

 that we know full well that they often spoil the sport in a river- 

 Can it be supposed, for a moment, that a salmon in these early 

 stages, during which periods of its existence it does not make any 

 great growth, feeds voraciously, and, after going to the sea, takes 

 either no food or very little, notwithstanding that the " smolt " 

 which leaves the river weighing only a very few ounces, returns 

 very soon as a grilse of several pounds ? It seems unreasonable. 

 Some smolts return from the sea as grilse in about three 

 ' months, whilst others of the same brood remain in the sea for 

 ! about fourteen or fifteen months. Those which return in about 

 three months have, taking a very low estimate, reached a weight 

 of some three pounds, but those which remain for fourteen or 

 fifteen months do not necessarily attain a very much greater size 

 than those which return in the shorter period. The same 

 peculiarity is noticeable to an extent amongst trout. Some 

 grow very much more rapidly than others. A smolt let off at 

 Stormontfield in May returned in July of the same year, weighing 

 about three pounds. On the other hand, one which the Duke of 

 Roxburghelet off on May i4th did not return till July of the following 



