208 



ANGLING. 



the king of beauty, presenting as he does (the 

 Apollo Belvidere of fishes) a picture so complete of 

 energy and grace combined. The fins of a trout 

 are of moderate strength, and always coloured, that 

 is, never of the transparent paleness observable in 

 certain migratory species, and the tints of these 

 parts are usually of a lighter shade than those of 

 the other portions of the body ; the anal fin is fre- 

 quently bordered on its lower surface with white ; 

 the tail is almost always forked ; the scaling is pro- 

 portionally less than among the migratory kinds ; 

 the teeth are generally strong, and very prominent 

 both on tongue and vomer. 



Some curious observations have been made both 

 by naturalists and anglers, on the sudden or almost 

 instantaneous alteration effected in the colouring 

 of fishes, simply by a change in their position, as 

 they pass from a lighter to a darker ground, or vice 

 versa. Dr. Stark found, in relation to fishes in 

 confinement, that when minnows were placed in a 

 dark vessel, their colours became assimilated to 

 that of the vessel, and that when transferred to a 

 white basin they " uniformly became in a very 

 short period of a light sandy colour, and their 

 characteristic markings disappeared." He repeated 

 the same experiments with the stickleback, of which 

 the changes of colour were " still more remarkable 

 than those of the minnow, in as much as they 

 took place much more rapidly ; and even in a few 

 minutes, and under the eye, the colours may be 

 seen to fade or brighten according to the nature of 

 the vessel they are placed in for a time. The fine 



