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direct their attention to the introduction of new and valuable kinds, as well as preserving and increasing those already existing in our rivers, bays, and salt-water creeks—for fish fall an easier prey to man than the beasts and birds, being more distinguished for the size of their heads than for the amount of brains lodged in them. The range of fish is very various; some are migratory in their habits, others stationary. Among the fresh-water fish, some inhabit waters of a purer or impurer kind; the salmon, trout, and others inhabiting the purer streams, whilst the eels and other species luxuriate in the more stagnant pools.
Artificial ponds for the maintenance of fish is a very early invention, and was even known among the ancient Egyptians. Vivaria among the ancients are mentioned by Columella, Varo, and Pliny, and fish was brought from a great distance; and an extraordinary fact is mentioned by Columella—that rivers and lakes were turned into natural vivaria, by carrying to, and depositing therein, not fish only, but the spawn of all such species as, though born at sea, are in the habit of penetrating some way up estuaries or streams. He speaks of the perfect success of the experiment in several rivers.
Various kinds of fish have been and are still being introduced, by preserving the ova, into different waters of England and on the continent, in localities where previously they had no existence; they have succeeded well, and where congenial food is plentiful the result is perfectly satisfactory. Alluding to the food of fishes, at one time it was a popular idea that salmon only lived upon microscopic animals; the reason of this error was, that the salmon, like most fish, expel the contents of the stomach when harpooned or hooked. It is an instinctive act to lighten themselves, and make easier their efforts to escape; and I believe it to be common to the whole class. This is the reason why salmon, when caught, never have any food in the stomach, wherefore some sagacious physiologists have conceived that this rich and delicious fish was fattened, forsooth, upon microscopic entomostraca, crustacea visible only to the naked eye in minute specks, when every one of the hundred-and-odd teeth of the salmon is bigger than some hundreds of these minute crustaceans.
The Australian blacks on the coast are expert fishermen, and Mr. Edward Hill, who possesses much information on the subject, informs me that when the beautiful waratah or native tulip blooms, it is a well-known sign to these children of nature that the sole (a rare fish to be seen in the Sydney market, but of
