Page:The Zoologist, 4th series, vol 2 (1898).djvu/413

Rh than that of arterial blood; but there is no reason to suppose that the colour of the blood is in itself any advantage; and though it adds to the beauty of the maiden's cheek, no one will pretend that it has been acquired for this purpose."

All our present knowledge of animal colouration is derived from motive; show us a practical use for the same in the creature's life, either in "protective and aggressive resemblance or mimicry," or in warning or nuptial colours, and the same is at once found to dovetail in that marvellous intellectual conception of this our time, so well known as Darwinism. But let the purpose be unknown, as is the general rule,—though probably no form exists in nature but is the outcome of use, now, or once,—and explanation reaches the standard of pure and scant hypothesis, scarcely to be avoided under the limitations of our present knowledge, nor to be condemned in the absence of experimental test. Poulton has advanced the proposition that the bright hue of many Sea Anemones may be explained under the term and theory of " warning colours," and that—based on experiments made by Garstang—the tentacles of Sea Anemones were distasteful to fish. But we learn from Mcintosh and Masterman that "it is a well-known fact that adult Cod are extremely fond of Sea Anemones, and some of the rarest species may be procured in their stomachs;" also that Sea Anemones are a favourite bait for Cod in some parts of Scotland. Darwin has pointed out how colour and constitutional peculiarities go together, and he learned from Prof. Wyman that in Virginia the Pigs were all black because they "ate the paint-root (Lacnanthes), which coloured their bones pink, and which caused the hoofs of all but the black varieties to drop off." Superabundant vigour in the male sex often produces excess or rather extra-development in colour, "as a cock Brambling will occasionally assume a black throat, or a cock Sparrow a chestnut breast, or a Rose Pastor a a reddish head." Although colours in fruits and plants have in many cases an equally important function as in animals for