fourth day.] VARIETIES OF SALMON . 113 



the salmo solar, or salmon, and salmo trutta, or sea 

 trout, in the rivers of Britain and Ireland. The 

 whitlings I believe to be the young of the sea trout. 

 A sea trout which I saw in Ireland, called a bull trout, 

 was of the same kind as these vou see here ; but fresh 

 water trout are sometimes carried in floods to the sea, 

 and come back larger and altered in colour and form, 

 and are then mistaken for new species : and as each 

 river possesses a peculiar variety belonging to it, this, 

 with differences depending upon food and size, will, I 

 think, account for the peculiarities of particular fish, 

 without the necessity of supposing them distinct 

 species. I remember many years ago, the first time I 

 ever fished for salmon in spring in the Tweed, I caught 

 with the fly, one fine morning in March, two fish 

 nearly of the same length : one was a male of the last 

 season, that had lost its milt ; the other a female fresh 

 from the sea. They were so unlike, that they did not 

 appear of the same species : the spent or kipper 

 salmon was long and lean, showing an immense head, 

 spotted all over with black and brown spots, and the 

 belly almost black; the other bright and silvery, 

 without spots, and the head small. Even the pectoral 

 and anal fins had more spines in the newly run fish, 

 some of the smaller ones having been probably rubbed 

 off in spawning by the other. I would not for some 

 time, till assured by an experienced fisherman, believe, 



