This
volume presents a broad panorama of the current status of research of
invertebrate animals considered belonging to the phylum Cnidaria, such as hydra, jellyfish, sea anemone, and coral. In this book the Cnidarians are
traced from the Earth’s primordial oceans, to their response to the warming and
acidifying oceans. Due to the role of corals in the carbon and calcium cycles,
various aspects of cnidarian calcification are discussed. The relation of the
Cnidaria with Mankind is approached, in accordance with the Editors’ philosophy
of bridging the artificial schism between science, arts and Humanities.  Cnidarians' encounters with humans result in
a broad spectrum of medical emergencies that are reviewed. The final section of
the volume is devoted to the role of Hydra and Medusa in mythology and art.