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then there were more such risings and expressed convictions. At intervals only, however, for it was wonderful how still the young birds would lie for quite a long time, and so closely inwoven within the cup of the nest that it was only when they stirred that five became a possibility. The ledge being quite bare and open, the nest with the young in it, making a black bull's-eye in the midst of a great sheet of white, was conspicuously apparent. Several times I saw the young birds move themselves backwards to the inner edge of the nest, and then void their excrements over it, so that only a little of the quite outer portion was contaminated. By this means the nest is kept clean and dry, whilst all around it is defiled. It would seem as though this power of ejecting their excrements to a distance which various birds possess was, sometimes at least, in proportion to the size and bulk of the nest which they construct. The nest of the shag, for instance (and in a still greater degree that of the common cormorant), is a great mass of seaweed and other materials, and the force with which the excrement is shot out over this, both by the young and the parent birds, astonishes one, as does also its upward direction. I had always felt surprise when seeing cormorants and shags perform this natural function whilst standing on the rocks, but it was not till I had watched the latter birds for hour after hour, as they sat on their nests, that I understood (or thought I understood) the significance of it. In spite of the popular saying, it does not seem probable that all young birds act in this way, and many nests are so constructed that it would hardly