THE SENSES OF FISHES. . 11 



posed. On the other hand, a pike could see much further 

 behind and backward than a trout. Indeed, the practice 

 of up-stream fly-fishing, to which I record my own attach- 

 ment, is based on the theory that the trout cannot see 

 behind it but an exceedingly short distance. 



Taking the trout as a fish not likely to seriously vary 

 in regard to its faculties and their possibilities because of 

 habitat, let us endeavor to ascertain the range of this 

 power of vision, both in the light of what has been 

 said, and what follows. First, one small but important 

 fact has to be noted as bearing collaterally but interest- 

 ingly on the subject. The fish is hard to frighten by 

 means of any object it sees in water only, as separate and 

 distinct from its cause or connection in air, if such exist. 

 To make this plainer : If an object be presented so that 

 another person, besides the presenter, can see its reception 

 by the fish (himself unseen), that person will notice it 

 seldom happens that the trout retires or darts away un- 

 less actually or positively touched say with the point of 

 a rod. Even then, so that the impact be gentle, he is not 

 alarmed, and this fact is taken advantage of by the " grop- 

 ing" poacher of Europe, who gently places his hand un- 

 der the trout lying with its eyes buried in the weeds 

 thinking itself secure, as does the ostrich when it buries 

 its head in the sand and lifts it suddenly to the bank. 

 Be the object presented a stone or a fly, so that its con- 

 nection with the arch* enemy of fishdom be not discov- 

 ered, the fish fears not. Its brilliant, infallible visual 

 faculty has apprehended the innocuousness of the object, 

 per se, and no fear is aroused. 



Try the experiment with the operator in full sight. 



