TROUT FLY-FISHING IN AMERICA 



ground lakes, a similar cause and like effect constantly exists ; the 

 fish cannot see, for they live in perpetual night. Why trout are 

 found in their native waters on which the glare of the sun or the 

 subdued light of the forest gloom are constant conditions, the fish 

 being without characteristic red spots, and now and then assum- 

 ing the abnormal coloration of the albino, is a difficult matter to 

 explain; it doubtless arises from the defective action of the nerve of 

 the eye upon the color glands, or petals, which lie under the scales 

 and which open and shut when under the influence of color tints 

 conveyed to them through the delicate nerve of the eye; certain 

 nerve fibres in such cases producing the red spots on the trout and 

 the diseased condition of others resulting in albinos." 



It may be that Mr. Harris is quite correct in his con- 

 clusions that the eye is the chief element or factor by which 

 trout coloration is produced and likewise controlled. 



While my own investigations, experiments, experience 

 and observations have led me to entirely different conclu- 

 sions as to the causes of coloration in trout, I do not wish 

 to be understood as saying that Mr. Harris is entirely 

 wrong simply because our opinions differ. 



That the eye has some effect upon coloration is unques- 

 tionably true, but to what extent it influences coloration 

 and controls it, is the point upon which we differ. 



My study of trout coloration has been such as to make 

 me believe that the eyesight of trout plays but little part in 

 color development, except in the case of complete blind- 

 ness, and then only in a secondary, not primary, sense. In 

 nature it is most rare to find blind trout, and it certainly is 

 not common to find them with impaired eyesight, although 



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