CHAPTER XII 



THE SALMON 



The Salmon— The Alevin Stage— The Parr Stage — The Smolt Stage — The 

 Grilse Stage — Habits of Salmon — Salmon Leaps — Do Salmon Feed in 

 Fresh Water? — Seasonal Change in Appearance — Process of Spawning — 

 Kelts — Rate of Growth of Migratory Salmonoids — Artificial Incubation — 

 Restoration of Salmon to the Thames — Salmon Disease — Early and Late 

 Salmon Rivers. 



Fifteenth Family : SALMONID^: THE SALMON FAMILY 



By far the most important of our fresh-water fishes, 

 both from an economical and from a sporting point of 

 view, are the Salmonida. Without troubling the reader with 

 an anatomical analysis of the family, it may be mentioned 

 that its members are easily distinguished from all other 

 fish in British waters by the possession of two dorsal fins, 

 whereof the second is always rudimentary and without rays — 

 thick and fatty, hence called the adipose, or dead fin. This 

 is the badge ot the family, merely an envelope of skin con- 

 taining nothing but gristly and fatty matter. Species of 

 Salmonida inhabit both the sea and fresh water, as well as 

 other species which perform a regular migration from one 

 to the other ; but, with a single exception, the fresh-water 

 and migratory species are confined exclusively to the temperate 

 and arctic zones of the Northern Hemisphere. The exception 

 is a remarkable one — a small smelt [Retrofinna Richardsonii^ 



inhabiting certain lakes in New Zealand. 



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