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1] I will therefore only quote the case of New Zealand. The rainbow trout was introduced into both islands, but while it thrived amazingly in the warm waters of the North Island, it has proved a comparative failure in the cold waters of the South Island.
[1] The Rainbow Trout. Lawrence & Bullen, London.
While the common or brown trout (Salmo fario) and the rainbow trout (Salmo irideus) are, in my opinion, to be strongly encouraged in the waters suitable to their respective qualities, the American brook trout (Salvelinus fontinalis) does not seem to have met with the approval of most of the authorities on pisciculture in this country. My experience of this fish is not sufficient for my holding any very strong views with regard to its suitability to British waters. In one case I know that it was a great success for two seasons, but I have not had any opportunity of following it up in this particular instance. In another case it was a decided failure. I am sure that it should not be introduced into streams where brown trout thrive, and I am doubtful of its ever succeeding in waters which are suitable to the rainbow trout.
Of all the trout, the rainbow is the hardiest, and the one with which the amateur pisciculturist is most likely to be successful. It is also the fish most likely to supply a want felt by very many fishermen, a good sporting fish in waters where the common trout will not thrive.
In large and deep ponds with a good stream, or in lakes, char may be tried with a prospect of success. They require cold waters, and I have never heard of their being successfully introduced in the South of England. They are a more difficult fish to rear than trout.
Grayling have many violent opponents, but I am inclined to think that they do but little if any harm in a trout stream, and they supply excellent fishing during part of the close season for trout. They seem to thrive best in chalk streams, but there are no doubt many waters which would car