Page:The Zoologist, 4th series, vol 2 (1898).djvu/486

454 streams about Winchester, are of a beautiful silvery colour. Gudgeons placed in a glass bowl will become very white, and lose the beautiful brown colour on their backs." "A fishmonger at Billingsgate Market told me he generally knew from what part of the coast fish came by the colour of them. This observation was à propos to a quantity of Dutch Jack that were displayed on his slab; and which looked very dingy and dark-coloured, as though they had lived in stagnant and dirty water; very different from a clean and bright-coloured Thames Jack." "Sticklebacks are wonderful fish to change their colour. I have seen Sticklebacks at the tail of a mill pond at I slip of the most beautiful iridescent colour; the bottom was composed of clean white gravel stones. Again, there is a ditch running round Christchurch meadow at Oxford; here the water is black and dirty, and the Sticklebacks are of a brown and almost black colour." The same author considers that "the Black-backed Salmon" of the Galway river "are fish which have spent most of their lives in dark bog-coloured water, and hence they have assumed the peculiar dark appearance they present, for, as we all know, the colour of the fish is wonderfully influenced by the colour of the water in which it lives." There is a well-known rock on the coast of Cornwall, about five leagues from the land, and standing up from the plain ground which spreads to a large distance round it. The top of the rock is full of gullies shaded with weeds, and Congers which are caught on it are always black, while close to its base these fish are always white. From Great Yarmouth it is reported that Flounders (Pleuronectes flesus) when sea-caught are lighter hued than those taken on a muddy bottom. "The Sunfish (Labrus auritus, Linn.) caught in the deep waters of Green River in Kentucky exhibit a depth of olive brown quite different from the general tint of those caught in the colourless waters of the