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 CHAPTER III

FROM DARKNESS TO LIGHT

O all that I have said concerning the Arctic skua in my last chapter (I do not say it is much) I will now add what the Germans call a Beitrag, on the subject of the multitudinous variety of colouring and arrangement of markings which the plumage of this species exhibits.

Hitherto, indeed, I have spoken as if it were always of a uniformly dusky shade, but that was because I wanted that shade (and, indeed, it happened so to be) in the two that were chasing my tern. Otherwise they would not have suited the part I assigned them of twin evil geniuses, or have contrasted sufficiently with the white soul that they were seeking to corrupt. So, till that was all over, there could be no light or half-light skuas, but now that it is, and the effect produced, I permit things to be as they are.

The Arctic skua, then, is supposed by ornithologists—or, at any rate, that is how they are accustomed to speak of it—to be a bird of two different outer appearances, independent of sex, which does not add another one: dimorphic we are told it is, which means, or should mean, that it is two- or double-formed, taking form here to mean colour. Two! A hundred would be nearer the mark, I think, but I 15