198 GROWTH OF SALMON AT SEA. 



return to its natural element, fresh water, it will 

 in all probability, and no specific circumstances 

 preventing, have increased by the end of that 

 time, to the weight of five pounds or more. So, 

 if the growth of salmon during the first year of 

 their existence, is extremely tardy in fresh water, it 

 is, after that age, more than proportion ably rapid 

 in salt water. It will be well to bear in mind 

 that the growth of salmon is not always propor- 

 tioned to the length of time they sojourn at sea. 

 Several circumstances affect their rate of physical 

 development. Amongst others, indeed they are 

 the chief ones, quality and quantity of food found 

 on the salt-water feeding grounds, and hereditary 

 capacity for growth. By " hereditary capacity," 

 I mean that the offspring of large fish have the 

 inherent power of growing, and do grow,* to a 

 larger size than the young of small salmon. When 

 I speak of large and small salmon, I refer to fish 

 which eventually become very large, and to fish 

 which, no matter what their age, will always be 

 small ; in fact, to giant and dwarf breeds. The 

 growth of salmon-fry is pretty equal in all rivers ; 

 and, therefore, smolts, no matter whether they are 

 the produce of large or small salmon, will be found 

 in different rivers, not differing much in size. 

 Such is not the case, however, after the smolt 



