124 DISPUTES OF THE "DOCTORS." 



CHAPTER VII. 



" When doctors disagree, 

 Disciples, then, are free." 



OLD ADAGE. 



IN this chapter we shall present our readers with 

 what we deem an ample list of flies for all the 

 rivers in the kingdom, and also with a full enu- 

 meration of the various materials of which each 

 particular fly should be composed, premising a 

 few remarks on imitation, a subject upon which 

 much diversity of opinion exists. 



We have quoted, in our second chapter, the 

 theory of Professor Rennie, which is directly 

 opposed to the notion of exact imitation, and to 

 that of the fish taking an artificial fly in mistake 

 for a peculiar species of its own natural prey. The 

 grounds on which that theory is founded, namely, 

 the defective vision of fish, and consequently 

 their physical inability to distinguish the different 

 species, even if they had a preference for parti- 

 cular kinds, are also given at length ; and on this 



