A prosaic, but very informative guide to the physiology, life cycles and learning behavior of the mollusks by the expert author of Animals Without Parents (1970). The lion's share of attention is devoted to the many varieties of snails which are the most numerous class of mollusks, and (despite occasional sidelights on their usefulness to man and on the work of specific researchers) the emphasis is on a thorough descriptive review of each species. The ""mollusk observations and experiments"" (again dealing mostly with snails) outline some ambitious, potentially rewarding projects, and the bibliography lists a broad selection of books and magazines on both the juvenile and adult levels. More photographs and schematic drawings could have been included (we'd like to see that poisonous cone snail, for example), but those which appear are functional and well chosen. A comprehensive manual for the experiment-oriented student.