Page:Popular Science Monthly Volume 15.djvu/388

374 faintly purplish blue, would not have exhibited those splendid eye-like spots which reflect the sunlight in a mingled mass of glory from this perfect tail-covert. Only in the most fitting positions for decoration do birds, as a rule, expend their choicest designs.

The feathers of the ostrich naturally occur first to the human investigator of æsthetic taste in birds. The quills of the wing and tail, here purely ornamental in their function, compose the well-known silky plumes of commerce. The common crane has also beautiful elongated wing-feathers, which fall on either side of the tail in graceful waving masses. If we may trust the doubtful pictures which have come down to us, that grotesque and gigantic pigeon, the dodo, possessed similar tufts of ornamental plumage. But the great order of gallinaceous birds, or the hen and turkey tribe, display the most magnificent tails of all, so familiarly known in the peacock and the pheasant family, as well as in the humbler denizens of our English farmyards.

Crests form another favorite ornamental device among birds, occurring independently in the most different orders. The graceful tuft of the gray heron must have attracted the attention of every observer. Among the pheasants similar decorative adjuncts are common; and the curassow shows this peculiarity in a very beautiful form. With parrots and cockatoos, crests are of frequent occurrence, and they make equally striking features among the humming-birds and sun-birds. Indeed, it may be roughly asserted that those birds which seek their food among flowers and fruits, and which consequently exhibit a taste for bright colors, are also the species in which ornamental tufts of feathers most frequently occur. But crests are also found even among the generally somber and inartistic birds of prey, being by no means unusual in the owls and hawks, while the serpent-eating secretary-bird derives his queer name from the fancied resemblance of his top-knot to a pen stuck behind the ear. Other well-known instances of crested species are the hoopoe, the wax-wing, the golden-crested wren, and many jays. But the umbrella-bird, a Brazilian fruit-crow, exhibits the fullest development of this particular ornament, having the whole head covered by a dome of slender, shining blue feathers, about five inches in length by four and a half in breadth. It may be added that almost all birds which possess these ornaments possess also the power of raising or depressing them at will; and that during the season of courtship the male birds constantly expand all their charms before the eyes of their admiring mates. We have all seen this ostentatious display ourselves in the case of the peacock, the turkey, and the barn-door fowl. It proves almost beyond a doubt the aesthetic purpose and