178 APPENDIX. 



M. Do you believe that all the grilse and salmon that come 

 into a river spawn ? 



H. As a general law of nature, all animals are subservient 

 to the instincts and functions placed in tiiem ; and if salmon 

 were not disturbed in the rivers, either by floods or by man, 

 they would all accomplish the object for which they came to 

 the rivers ; but they are so frequently interfered with and in- 

 terrupted in the process of their spawning operations, that all 

 those who do not get that process accomplished before the 

 middle of December have their object frustrated, and the 

 spawn becomes vapid ; so that if the ova in the salmon, called 

 " bag gits" caught in the Tweed in the month of February, 

 were to be conveyed to an experimental pond, my belief is, 

 that it would prove addled and of no avail, as it would be an 

 anomaly in the laws of nature to suppose that salmon had the 

 power of prolonging the time of gestation to an indefinite 

 period. 



M . When do the parent fish leave the river ? or is it neces- 

 sary for them to superintend the education of the young fry ? 



H. They quit the rivers by degrees, extending over all the 

 spring months, nor do they evince any great solicitude for the 

 fry ; if they did, they would require to remain in the river six- 

 teen or seventeen months : but such solicitude is not necessary, 

 as their instincts lead the young smolts in their journey to 

 their destination. A more convincing proof of the powerful 

 action of instinct can in no instance be more apparent than in 

 the cuckoo. It makes its appearance about the commencement 

 of May ; it has never yet been known to build a nest for itself; 

 it deposits its egg in another bird's nest, and disappears before 

 its progeny has quitted its foster-mother's guardianship. Yet 

 a few weeks thereafter the young bird also mysteriously dis- 

 appears, without any assistance or guide but the force of in- 

 stinct ; showing that the same instinct leads to the same result, 

 though not simultaneously. I could state some interesting 

 facts relative to cuckoos ; but that would be entering into de- 

 tails which is not my object, either as regards the salmon or 

 the illustrations brought forward, to elucidate the mystery that 

 obscures the difference between salmon and grilse. 



