of-paradise, and parrots, induces the belief that in these classes the exercise of the structures upon the search for food has led to the formation of a very strong taste for color, ultimately resulting in sexual modifications.
As for the harmony of color usually observable in birds, it must be remembered that our feeling of harmony probably depends upon the due intermission and alternation of sense-stimulants, and therefore ought naturally to be shared by us more or less definitely with all other animals having a like constitution of the eye. Now, the mammalian and avian eye being derived from a common ancestor, who already possessed a highly developed power of vision, we might reasonably expect that our feelings of harmony would be essentially identical; and this expectation is fully borne out both by the coloration of fruits and of birds themselves, which seldom or never present what we should regard as discordant coloring. Furthermore, as the most beautiful classes of birds are those which live perpetually among tropical flowers and fruits, in the most beautiful forests or meadows, surrounded by exquisite insects and reptiles, and for ever exercising their vision upon the most diversely colored environment in the whole world, it would seem far from impossible that their chromatic sensibility is even more highly developed than that of average humanity, and therefore that harmony or discord of colour would bear a relatively greater importance in their eyes than in those of any human being except the most artistically endowed. This conclusion will doubtless sound strange and even grotesque to those who are always accustomed to postulate for man a kind of absolute supremacy in the scheme of Nature; but it appears to me almost as obvious and as simply accounted for as the superiority of scent in the dog and the deer, or of distant vision in the eagle and the vulture. Lastly, it may be noted that much of the beauty of birds, as of insects, fruits, and flowers, is due to the delicate gradation of tints which they display. But in all natural products such gradation is an almost necessary result of the mode by which they have been evolved. It is only in human manufactures, where pigment is laid on with a brush or stamp, that colors can be placed in crude juxtaposition to one another, giving rise to the worst form of chromatic discord. Doubtless our native feeling of dislike to such discords, based upon their immediately fatiguing effect upon the nerves employed, has been heightened intellectually by the knowledge that they differ so widely from the dainty gradations to be found in the handiwork of Nature. Besides being sensuously recognized as discordant, they are intellectually recognized as inartistic. Thus a large part of our art-progress has consisted in an advance from the harsh and monotonous fields of primary red and blue, divided by very hard and definite lines, which we find in Egyptian painting, to the faithful representation of graduated tints and shades which appears upon a modern canvas. But in the petal of a rose, the ray of
