The marine zooplankton is one of the most fascinating and diverse assemblages of animals known to biologists. This is a new edition of the successful student's manual providing a photographic guide to representative forms of the major groups from medusae and comb jellies to larval fish and squid. In it, only live and active organisms have been photographed, giving a unique visual perspective. In this new edition, the taxonomy and morphology have been revised and brought up to date, so that combined with information on behaviour and development, this book creates a vivid and essential reference text for all those interested in marine zooplankton.