42 BRITISH FRESHWATER FISHES 



Clean Fispi. — Silvery fish with firm flesh and 

 the sexual organs little developed. 



Unclean Fish. — Fish which are nearly ready 

 to spawn, or which have recently spawned. 



Red Fish. — Ripe male Salmon. 



Black Fish. — Ripe female Salmon. 



Kelts or Slats. — Spent Salmon; if these 

 stay in fresh water they become more or less 

 silvery and are termed Mended Kelts. 



Some of these names explain themselves, but the 

 meaning of others is uncertain. Grilse corresponds 

 to the Scandinavian Gralax, Grey Salmon. Parr is 

 from the old English parren^ to enclose, from the 

 resemblance of the marks on the sides to the bars of 

 a fence, and Graveling is doubtless connected with 

 the habits of these young fish, which frequent 

 gravelly shallows. Smolt is from the Anglo-Saxon 

 smeoit, shining, in allusion to the silvery colour. 



Not long ago the history of the Salmon was very 

 obscure, but investigations made in recent years 

 have cleared up so many points that now we 

 perhaps know more of the life of the Salmon than of 

 most other fishes ; therefore, some account of the 

 methods by which this splendid result has been 

 obtained will not be out of place. 



The problem of what the fish did from the time 

 they went down to the sea as smolts until they 

 returned as grilse was solved by a Norwegian, Herr 

 Dahl, who adopted the plan of fishing for them with 

 suitable nets in likely places until he found them in 

 the open sea, following the shoals of young Herring, 

 Smelts, Mackerel, etc. ; by this same method of 

 continued fishing throughout the year, finding out 



