THE TROUrS 



has been planted with moderate success in some of 

 the waters of the Eastern and Western States. It 

 takes its name from the old lake adjoining the dis- 

 mantled castle within which Mary Stuart was im- 

 prisoned by Queen Elizabeth. It is very closely 

 allied to the brown trout, and is a beautiful and 

 gracefully formed fish, and is said to be distin- 

 guished from the brown trout by the absence of 

 red spots on the body which, however, appear on 

 specimens more than four years old, but so dimly as 

 scarcely to be seen. This peculiarity of coloration 

 is disputed, and yet it may be another illustration 

 of the effect of food and environment on the color- 

 ing, markings, and form of fish. 



The rainbow trout [Salmo irideus) is a native of 

 the mountain streams of the Pacific slope, where 

 six different species exist, all differing somewhat 

 widely in coloration, form, and size. The distin- 

 guishing mark, however, which in various degrees 

 of color may be seen on all the species, is a reddish 

 lateral band, which disappears when the fish visits 

 salt water. 



The fish savants partially differentiate these six 

 species by the number and positions of the black 

 spots, which on many specimens are found to be 

 very numerous. The rainbow that has been intro- 

 duced into eastern waters is the species from the 



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