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Rh name, though not wholly deserved—having been, originally, a plain homely-coloured bird, like his relative, the great skua, is being gradually modified, under the influence of sexual selection, into a most beautiful one, as represented by the extreme light or half-cream form. Natural selection, in the more general sense, seems here excluded, or, at any rate, extremely doubtful; and if it be suggested that the lighter birds have the more vigorous constitutions, that they are fuller of verve and energy, to which they owe their cream colouring, I, for my part, can only say "Prodigious!" (or think it), like Dominie Sampson. But I can assure all those who hold this unmanageable view—for really there is no dealing with it—that the one sort came not a whit nearer to knocking my cap off than did the other. But, leaving shadows, the main facts here suggest choice in a certain direction. There is a gradation of colour and pattern, connecting two forms—one plain, the other lovely. This suggests a passage from one to the other, and if the plain mature form—I mean the uniform brown one—most resembles the young bird in colouring—which to me it seems to do—whilst the young bird resembles, more than any old one, an allied plainer species, this makes it more than likely that the passage has been from the plain to the lovely, and not from the lovely to the plain. Supporting and emphasising this, we have the absence, in the tail of the young bird, of those lance-like feathers which give so marked a character to, and add so infinitely to the grace of, the