The Development of Modern Fish Culture. 175 



was a rise from a fish which was evidently a good deal bigger, and 

 it soon became apparent that we had hooked one of the larger 

 fish. This was led into the landing net with hardly a protest, and 

 it was indeed a pathetic sight. To say that the fish was thin and 

 lanky conveys no idea of what it looked like ; it was reduced to 

 the point of emaciation. 



A knowledge of the natural conditions prevailing in this loch 

 would have enabled the fish culturist to avoid a mistake of this 

 kind, and the size of the native trout would have been the first 

 thing to call his attention to the fact that all was not as it should 

 be. He would have investigated the reason for this state of 

 affairs, and would very speedily have found that the remedy did 

 nol consist in the introduction of large trout but in a preliminary 

 course of food cultivation. 



Strange though it may appear, many people, without having 

 thought much about the matter, have jumped to the conclusion 

 that good water is all that is necessary for the production and 

 maintenance of good trout, whereas the truth is that the water 

 stands in the same relation to the fish as the air stands to us. It 

 is the medium in which they live. The food supply for the trout 

 in the water and the quality of it determine the size the trout will 

 attain and the rapidity of their growth. This food supply is 

 composed of many kinds of small creatures such as water beetles, 

 larvfE of flies, raollusca, various Crustacea, the most valuable being 

 the fresh water shrimp, and, as everyone knows, flies. When the 

 food question has been brought to notice a common mistake has 

 l)een made in thinking that it is only necessary to introduce this to 

 at once put matters on a satisfactory footing, but it is essential to 

 remember that even as the trout require food .so do the creatures 

 of which this consists. 



It is precisely at this point that difficulties arise. Most of 

 the creatures on which trout feed are dependent on various forms 

 of vegetable growth, and those that are not are dependent for 

 their food on other creatures that are, so that we are driven to a 

 consideration of these vegetable growths and the conditions under 

 which they thrive. This, one might be tempted to say, is a 

 simple matter, and so it would be if we only had to deal with the 

 common aquatic vegetation which may be found in any ditch, but 

 it is with the delicate and almost invisible algae which grow on 

 these plants that we are concerned, and we find that here a con- 



