226 SALMONIA. [NINTH DAY. 



river trout, or why there should be two species or 

 varieties in the same water. 



HAL. Your question is a difficult one, and it has 

 already been referred to in a former conversation; 

 but I shall repeat what I stated before, that qualities 

 occasioned by food, peculiarities of water, &c. are 

 transmitted to the offspring, and produce varieties 

 which retain their characters as long as they are 

 exposed to the same circumstances, and only slowly 

 lose them. Plenty of good food gives a silvery colour 

 and round form to fish, and the offspring retain these 

 characters. Feeding much on larvae and on shell- 

 fish thickens the stomach, and gives a brighter yellow 

 to the belly and fins, which become hereditary 

 characters. Even these smallest salmon trout have 

 green backs, black spots only, and silvery bellies ; from 

 which it is evident, that they are the offspring of the 

 lake trout, or lacks forelle, as it is called by the 

 Germans ; whilst the river trout, even when 4 or 51bs., 

 as we see in one of these fish, though in excellent 

 season, have red spots. But why that exclamation ? 



POIET. What an immense fish ! There he is ! 



HAL. I see nothing. 



POIET. At the edge of the pool, below the fall, I 

 saw a fish, at least two or three feet long, rising with 

 great violence in the water, as if in the pursuit of 

 small fish ; and at the same time I saw two or three 



