CRITICS of the current theory of mimicry, but only so far as butterflies are concerned, claim that published records are insufficient to establish birds as the agents which may be considered mainly responsible for the production of mimetic resemblance in butterflies by preferential feeding. The following observation, communicated to me by Mr. T. H. E. Jackson, of Kitale, Kenya Colony, is therefore of great interest to all students of natural selection. Early in the present year, at Bulumbe camp in Busia, in the eastern province of Uganda, he noted on the first night “a few wings of butterflies lying about but it was not until next morning that the truth dawned on me. I then found that the ground was literally strewn with wings. There were four or five large Spathodea nilotica trees in the compound and swarms of butterflies were feeding on the flowers. Watching them that morning for birds I saw one swoop down on a Papilio bromius and take it off to a bare branch where it proceeded to beat off the wings, devouring the body only, and then returned to the tree for more. I made a list on paper of the butterflies present and only afterwards thought of collecting the wings themselves as evidence: one Acraea we could not find again”.