18 THE FRESH- WATER TROUT. 



this point must be in a great measure conjectured, 

 and cannot well be tested by experiment, as trout 

 will hardly increase in size at all unless free to seek 

 their food and -range the water as they please. We 

 believe that a ten-year old trout may not weigh half- 

 a-pound, or may weigh six pounds, according to the 

 quality and quantity of its food. 



The number of trout a river produces depends 

 upon a variety of natural causes, the principal of 

 which is the spawning accommodation. Rivers in 

 which there are plenty of smooth gravelly stretches, 

 and which receive numerous small tributaries, gener- 

 ally produce numbers of trout shallow water and 

 a gravelly bottom being necessary for the deposit 

 of the spawn. If a river is scantily furnished with 

 spawning accommodation and also with food, the 

 trout will neither be numerous nor large ; the 

 Spey, the Dee, the Esk (Dumfriesshire), and most 

 Highland streams, are examples of this. If the 

 spawning accommodation is deficient and the feeding 

 good, the trout are large, as in most slow running 

 streams. If the spawning accommodation is good 

 and the supply of food limited, the trout are gener- 

 ally numerous but small ; Manor and Quair in 

 Peeblesshire, and some of the tributaries of the 

 Whitadder in Berwickshire, are examples of this, 

 in any of which the angler may easily capture from 

 ten to fifteen dozen of trout any day in summer. 



Small rivers produce more trout in proportion 

 to their size than large ones, as a large river has 



