FLIES FOR MAY. 91 



substitution of a thin black silk body. These 

 black flies resemble many small beetles, and may 

 be ranked among " general flies. " In fine low 

 water, after Midsummer, they are most useful, 

 in the rapid parts of streams. 



No. 21. THE OAK FLY. 



This fly may be found upon the trunks of any 

 kind of tree or post near the water side. As soon 

 as it alights, it turns its head downward. It is 

 in season throughout May and June, and may 

 be used with most success on windy days. It 

 kills well in the natural state, by dibbing with 

 it in the still deeps of trout rivers. 



IMITATION. 



BODY. Orange floss silk tied with ash- 

 coloured silk thread, which may be shown at 

 the tail and shoulders. 



WINGS. From a scapular feather of the wood- 

 cock. 



LEGS. A furnace hackle (i.e. a red cock's 

 hackle, with a black list up the middle, and 

 tinged with black also at the extremities of the 



