WATER INSECTS AND THE RISE 77 



late David Foster's " Scientific Angler."* It must 

 be something like twenty-five years since I first saw 

 a copy of this little book, and about thirty-five 

 since my cousin, the late Dr. Charles Wickham, of 

 Winchester, f first told me of the theory and I have 

 so far found it a never failing guide to the proper 

 selection of the likely fly, and also as increasing the 

 interest of one's fishing. Briefly the theory is as 

 follows : 



" That the Fishing Ephemeridae are all contained 

 in the limits of four distinct families, and that all the 

 Duns we fish with are governed by the rules 

 regulating these families. He holds that these 

 families consists in order of size : 



" i. The May Fly or Green Drake. 



"2. The March Brown. 



" 3. The Blue or Olive Dun. 



" 4. The little Iron Blue Dun. 



" It was of the two last I was talking, as most 

 concerning our ordinary trout stream in the South of 

 England. 



" Mr. Foster declared, and Dr. Wickham has told 

 me he had proved, that all the larger Duns were the 

 progeny of the Red Spinner, that is that the Blue, 

 Olive, Yellow and Ginger Duns are each according 

 to the time of the year, hatched out from the eggs of 

 the Red Spinner, and that the colour varied pro- 

 gressively according to the time of the year and the 

 temperature of the air and water. He found that 

 from the eggs of the Red Spinner laid in June, he 

 got: 



" In February, the Blue Dun. 



" In April, the Blue Dun with Olive Legs or 

 Cockwing Dun, varying on dirty days to the Dark, 

 and on fine warm days to the Medium Olive. 



* To be obtained from Messrs. Foster Bros., Ashbourne, Derbyshire, 

 price 2s. 6d. 



t The originator of that excellent fly, " Wickham's Fancy." 



