Reprinted from Field Studies, Volume 9, No.2 with the same pagination. This guide should enable most beginners to identify all of the 42 species of bony fishes that breed in freshwaters in the British Isles. It also includes the three lampreys which may be encountered – although these are not true fishes but are often mistaken for them. The guide includes ecological and distribution notes, and should be of use to anybody with an interest in fish.