Is there not even a fallacy in the argument against this bird which is supported by a note in NATURE of June 6, p. 271? You say that because 52 per cent. of the rook's food is injurious, 19.5 per cent. neutral, and 28.5 per cent. beneficial, therefore “it is impossible to ignore the fact that at present this bird does considerably more harm than good,” even though, as you admit, 23.9 per cent. of the rook's food consists of injurious insects.