206 DOMESTICATED TROUT. 



is caught in shady places over black, muddy bottoms. 

 And what is still more remarkable, trout have the 

 chameleon gift of almost instantly changing their tint 

 within certain limits.* 



They do not, strictly speaking, change their color, 

 because a black trout will remain a black trout and a 

 silvery trout will remain a silvery trout wherever you 

 expose them ; but a complete change comes over 

 their whole complexion, so to speak, as if the light to 

 which they are subjected were diffused through them, 

 so that, in passing from a dark, muddy bed over light 

 gravel, they will in less than a minute take the general 

 hue of the gravel, and vice versa in passing from 

 gravel to mud.t 



The natural food of trout is very various. They 

 are carnivorous from choice, though omnivorous in 

 emergency. Their food, when wild, consists chiefiy 

 of water insects, smaller fish, larv?e, fish eggs, Crusta- 

 cea, and the flies and insects which fall from the air 

 into the water, — all of them together forming an 

 astonishingly extensive variety. They also eat each 

 other, and there are some individuals which adopt 

 cannibal habits altogether, and remain hidden, like 

 spiders, in dark holes and corners, and only emerge 

 to devour their like. 



The quality of their food affects the growth and ap- 

 pearance of trout, and it is even thought that the dif- 



* The black bass and some other fish have the same power 

 to some extent. 



t This change takes place, not in the scales, but in the skin 

 underlying the scales. 



