60 BIRD-LIFE OF THE BORDERS 



rivers, there is a distinct spring-run and an autumn-run : 

 separated by a quiescent period during the summer. 



Without attempting to go into the larger questions 

 here raised, and which lie beyond the scope of this 

 book, I will briefly outline my ideas on the biology of the 

 salmon. 



In the beginning — that is, long before historic times, 

 greenheart rods and "black-doctors"- — the more enter- 

 prising of the genus Salmo, finding the competition of the 

 rivers inconvenient, and after successful trial forays in the 

 brackish estuaries, at length boldly ventured forth into the 

 open sea. The result in process of time was the evolution 

 of Salmo salar, the less enterprising individuals remain- 

 ing Salmo fario. Just as the bird- world (as suggested in 

 a former chapter) tend, at their reproductive season, to seek 

 the north as being, ages ago, their original home and centre 

 of dispersal ; so the evolved form of Salmo returns, by 

 hereditary instinct, to reproduce his race in the same 

 fresh waters wherein he was born. But how is it to be 

 explained that the salmon of each particular river have 

 their own particular ideas of the proper season to 

 return thereto ? There should be a reason ; yet none 

 is apparent — unless it be as suggested below. For their 

 return to fresh waters by no means coincides with the 

 period when they are due to spawn therein. On the 

 contrary, their habits in this respect seem absolutely 

 irrational and illogical, and certainly entail to the early- 

 run salmon many months of grave inconvenience and 

 discomfort for no visible object whatever. Instead of 

 roving the open sea, he deliberately coops himself up, 

 for all the long hot summer, within the narrow limits 

 of some still pool or hole. 



The spawning season of salmon is in mid-winter. That 



