A calm water surface on any freshwater habitat can support a community of animals and plants of great interest. Some live above the water but in regular contact with it, and others hang down from the surface. This handbook deals with the smaller invertebrate animals of this surface community. Among these are springtails, pondskaters, water boatmen, water beetles and water spiders, as well as protozoa, rotifers and tiny crustaceans. After giving a brief introduction to the surface forces that are so important to these animals, the book describes the natural history of the main groups of animals in this community, drawing attention to topics on which further investigation is needed. Consideration is given to the problem of pollution by oil and by detergent. Keys are given for the identification of surface-dwelling animals, either to the major group or, where possible, to the species. Methods of keeping and studying the animals are described.