28 SALMON FISHING IN THE TWEED 



confess they have discovered no variation of organic 

 structure. 



I have heard it objected that the growth of the 

 salmon being very rapid, it seems out of the order 

 of nature to suppose that a creature should remain 

 so long in fresh water with so little increase of size. 

 But salmon never grow in fresh water; on the 

 contrary, they begin to waste from the moment 

 they enter a river, whether they are clean at that 

 period, or forward in spawning. Besides, as the 

 full latitude of the spawning season endures for six 

 months, some of the fry, acknowledged by all to be 

 smolts, must be six months older than others, and 

 yet when they congregate to go to sea they will all 

 be found to be nearly of the same size. Now if the 

 fry, confessed by all to be smolts, or the young of 

 the salmon, do not increase during so many months, 

 why should it be objected that the parr is not the 

 young of the salmon on the same account ? 



These and other arguments have occurred to me 

 from time to time. All reasoning, however, on 

 this subject is now become superfluous ; Mr. John 

 Shaw of Drumlanrig having demonstrated, by a 

 number of careful and scientific experiments, that 

 the parr is actually the young of the salmon. His 

 first paper, announcing this important fact, was 

 published in the "Edinburgh New Philosophical 

 Journal" for July, 1836, vol. xxi. page 99. His 

 second was read before the Royal Society of 

 Edinburgh on the 18th of December, 1837, and 

 was published in the " Edinburgh New Philosophical 

 Journal" for January, 1838, vol. xxiv. page 165. 

 His third and concluding communication, by far 



