CHAPTER «tl 
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: SALMONIDAE: 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 Salmonide. 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 of the family, merely an envelope of skin con- 
taining nothing but gristly and fatty matter. Species of 
Salmonide 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 (Retropinna Richardsonit) 
inhabiting certain lakes in New Zealand. 
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