This book is a compilation of 97 selected papers. which were presented at the 5th International Conference an Coelenterate Biology, held at the University of Southampton (U.K.) in 1989. The volume is presented in 13 sections. each comprising a series of papers dealing with specific topics, and encompasses general reviews as well as important advances in research. The topics include: cellular biology with separate sections on nematocysts and skeletogenesis; developmental biology; reproduction; ecology;pelagic coelenterates; endosymbiosis; evolution and systematics with separate sections on palaeontology and biogeography; genetics, both molecular and population; physiology and behaviour, including transmitters, bioluminescence and sensory systems.