THE study of animal behaviour has a long and arduous history. It cannot, however, be claimed that either the scope of the subject, or its methods, have been clearly defined. In interest it ranges from the ecological facts of the interaction of animals and their environments, through the details of life-history and their physiological analysis, on to questions of perception, motivation, learning and adaptive behaviour. Its methods embrace those of the field-worker, those of the physiologist, and those of the psychologist. Its philosophy, again, is in some quarters undefined, in others aggressively, even if vaguely, teleological and organismic, and elsewhere frankly empiricist. With all this diversity, those outside the subject can scarcely regard it as more than a concatenation of discrete interests and different methods. For the same reason, those within it can scarcely be blamed if their activities cover but a very narrow part of the whole subject. Nevertheless, ever since the turn of the century attempts have been made, in societies and journals abroad, to integrate what is, after all, a distinct, even though very wide, field of scientific exploration.