How to obtain it. 285 



this is just why I wish to give a note of warning to those about to 

 enter upon the work. " Do nothing rashly " is a motto that it 

 would be well to observe in time. Nature provides for everything ; 

 not one little bit of mechanism is wanting, and we find the result 

 perfect. Take the flowers of the field or the fish of the sea as 

 examples. Any one of them is perfect in itself. It remains so, 

 and from generation to generation there is no perceptible difference 

 in a species, be it what it may. But Nature makes special 

 provision for this being so, and, unless we do the same, confusion 

 will be the inevitable result. 



It is true that we find monstrosities and malformations in the 

 natural world ; it is according to the laws by which it is governed 

 that it should be so. But we only find them perpetuated under 

 special and peculiar circumstances they may be called isolated 

 cases. Take, for instance, the tailless trout of Islay, or the 

 hunchbacks of Plinlimmon, to both of which reference has already 

 been made. These are cases of fish living in pieces of enclosed 

 water where they are very much separated from the rest of their 

 species, and this probably accounts for the apparent discrepancies, 

 if they be rightly so called, but they end there they can get no 

 further. We find, then, that Nature provides for such discrepancies, 

 by arranging barriers beyond which they must not pass ; and, if 

 we take the trouble to investigate, we find that provision is made 

 for preventing them from spreading, and for the preservation of a 

 perfect race or type of fish. Nature, indeed, goes in for the 

 selection of the fittest. 



This, then, is what we ought to aim at in our work of 

 cultivating fish of any kind, viz., the preservation of a perfect race 

 1 or type. In order to do it, it is clear that we must take some pains 

 \to secure the best breeders. Having advanced so far, we have 

 the power given to us of still further improving the stock by 

 judicious crossing of the fish of different rivers. There is a large 

 field open for investigation here. We know the great advantage 

 of having good breeders amongst trout, and also of introducing 

 new blood, and there is no reason for supposing that salmon 

 should be made any exception to the rule which applies in such a 

 marked degree to trout. 



Let us turn our attention again for a few moments to those 



