x. PREFACE, 
upon the water at the time of fishing, still I am of 
opinion that an unnecessary number of patterns only 
confuses the tyro; the author gives a list of ninety 
varieties, I have gone through the whole carefully, one 
by one, and have come to the conclusion that from 
thirty to forty of them are amply sufficient to meet the 
requirements of the angler, not only upon the Yorkshire 
rivers, but upon any stream. Theakston has adopted a 
nomenclature entirely his own, and great has been the 
amount of both time and labour that I have expended 
upon the identification of some of his patterns; many 
of them are merely reproductions of different shades of 
the same fly, and it saves an immensity of trouble to 
adopt the plan in the first instance advocated by Mr. 
Francis, and later on by David Foster, viz., to keep a 
good stock of Browns, Duns, and Spinners of different 
shades, and adapt them to the various contingencies of 
water and weather. To such flies as I consider almost 
indispensable to the wandering angler I have appended 
foot notes, giving the name by which the fly is more 
generally known, and also any comments that I have 
thought might possibly prove of interest. 
For some of the information contained in those notes 
I must acknowledge my indebtedness to several sources, 
among which I may mention the works of Ronalds, 
Jackson, “ Ephemera,” and Blacker, also last, but by 
no means least, that splendid volume edited by Mr. 
W. H. Aldam, which illustrates, by means of actual 
dressed flies and their component parts, the patterns 
recommended by an old Derbyshire flyfisher who lived 
