THE SALMON, CHAR, AND VENDACE. 79 



tain this point. Fish were placed in three separate 

 tanks, one of which was supplied daily with worms, 

 another with live minnows, and the third with those 

 small dark-coloured water-flies, which are to be found 

 moving about on the surface, under banks and sheltered 

 places. The trout fed with worms grew slowly, and 

 had a lean appearance ; those nourished on minnows, 

 which, it was observed, they darted at with great greed 

 and voracity, became much larger ; while such as were 

 fattened upon flies only, attained, in a short time, pro- 

 digious dimensions, weighing twice as much as both 

 the others together, although the quantity of food swal- 

 lowed by them was in nowise so great. 



It is evident, from this and similar experiments, that 

 a very minute species of food is best adapted for the 

 growth of trout, and we do not see why salmon also 

 should not thrive upon a similar subsistence, found 

 in the salt water among marine weeds and shells, 

 and too small to be easily discovered in their stomachs 

 with the naked eye. 



We may notice, while treating of the salmo salax, 

 that the doctrine which holds the grilse to be a distinct 

 variety of that fish is now nearly exploded ; and it is 

 maintained instead, that both fish are of one and the 

 same sort, although in different stages of maturity. 

 This has been proved by practical experiments, and is 

 now beyond dispute. See the evidence of Murdoch 

 Mackenzie, William Stephens, and George Hogarth, 

 taken before the committee of the House of Commons 

 in 1825, on salmon fisheries. 



Yet, as to the herling, admitting it to be altogether 

 distinct from the white and sea trout (the salmo albus, 

 and salmo trutta), it is still with some a matter of con- 

 troversy whether it be a young salmon or not. We 

 have heard it alleged by anglers from Dumfriesshire, 



