does not try to cover all aspects of fish biology, but focuses on the ingenious ways in which fish have resolved the particular problems that come from living in water, especially body fluid regulation, locomotion, feeding mechanisms, and sensory systems. Enough detail is provided for the reader to be able to go on and use primary research papers. Each chapter has been thoroughly updated and a new chapter on the immune system has been added. This is an ideal textbook for students of fish biology and any of the branches of aquatic biology. Given its skilful combination of breadth and detail, the book also provides a manageable review of fish biology for experienced biologists.