BROOK TROUT 



minutes more to 85°, when it became convulsed, and, 

 although transferred to cool water, died. When the 

 water had sunk to 70° a smaller trout and a minnow 

 were put in, and although the next morning the tem- 

 perature had sunk to 67°, the trout was dead, but 

 the minnow had not suffered. A par of the salmon, 

 about four inches long, was similarly treated, the wa- 

 ter in half an hour being raised from 60° to 70°, and 

 now it tried to escape. The water was raised to 80° 

 and it became torpid and convulsed ; at 84° it seemed 

 to have died. A char of about the same size had the 

 water gradually raised to 80°, when it appears to have 

 succumbed. The trout tried to escape by leaping 

 out of the water, while the char kept to the bottom 

 with its head downward, as if seeking for a cooler 

 locality. 



The common brook trout of this country (fontinalis) 

 is a char, and undoubtedly acts as did the European 

 char in the experiment, by seeking cooler water down- 

 ward in a pond when the surface water becomes 

 warm, and searching out spring-holes in streams, so 

 they may be left to their own devices to find the cold- 

 est water provided in any stream or pond in which 

 they are planted; but unless the stream or pond con- 

 tains the cool water for them to find — i. e., below 70°, 

 and 65° would be better — it is useless to attempt to 

 propagate brook trout in it. There are other condi- 

 tions which operate against the maintenance of trout 

 in a stream. The fish must have gravel in which to 



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