A QUESTION FOR THE PHILOSOPHERS. 49 



perfectly abnormal, as are many matters in the 

 natural history of salmon, and of the sea- visiting 

 salmonidse. But dress those gaudy salmon flies, 

 or lake trout flies, as small as you like, and the 

 common trout and grayling will not rise at them ; 

 neither will dace, chub, nor roach ; and yet they 

 will rise freely at imitations of river-flies, cater- 

 pillars, house-flies, and flies that are bred upon 

 trees, amongst gravel, sand, and plants. I say 

 they will rise at these imitations, and rise at 

 them in preference to any other when the natural 

 insect they are designed to represent is on the 

 water or in season. 



Will the philosophers answer this question? 

 How is it that neither the common river-trout 

 nor grayling will, during the spring, autumn, or 

 winter months, rise at an imitation of the May-fly, 

 their especial favourite during a part of May and 

 June? If trout, or grayling, or chub would 

 prefer nondescripts to the imitations of flies on 

 the water, no more attractive nondescript could 

 be presented to them than the imitation of the 

 handsome May-fly when out of season. But they 

 never take it, except during the ' drake season,' 

 or a little before or a little after it, In that 

 season, viz. when the May-fly (Ephemera vulgata) 

 or green drake is out upon the waters, fish will 

 prefer an imitation of it to an imitation of any 

 other fly, except indeed of mornings or evenings, 

 E 



