Edmund Selous, The Zoologist (1899)
“ I, in fact, looked for the eggs upon the bird, for I knew the exact spot where they should be. But as I should have seen them at once, owing to their light colour, I felt sure that they must be covered, and, gazing still more attentively, all at once, by an optical delusion as it seemed, rather than by the passing away of one, the piece of fir-bark became the bird. The broad flat head, from which the short beak hardly projects noticeably, presents no special outline for the eye to seize on, but is all in one line with the body. ”
