88 OLD FLIES IN NEW DRESSES 



Does this ever happen to the sunk fly ? I 

 think not. In fishing across and down 

 stream it certainly does not ; and even in 

 up stream fishing, in order to keep his line 

 straight, the fisherman must keep a certain 

 amount of tension on it, and very probably 

 draws it through the water with much 

 the same sort of movement he would give 

 it if not fishing up stream. 



This movement through the water which 

 is given to the artificial must be absolutely 

 unlike any movement of the natural fly 

 when under the surface ; for in the natural 

 fly, if it were not already drowned, the 

 only possible movement would be that of 

 its legs and wings, which, not being in- 

 tended as a means of progression through 

 the water, and being absolutely unsuitable 

 for that object, would be most unlikely to 

 enable it to do so. 



But here a very natural question arises 

 as to what, if not the natural fly, the fish 

 takes the imitation to be? In a commu- 

 nication to the Field in June, 1897, I 

 described, under the heading of " A New 

 Trout Fly," the imitations of two Corixae. 

 This seems to be a key to the whole 



