With tentacles up to three metres long and covered with stinging cells, it's better not to get too close to the Lion's Mane jellyfish. The tentacles are arranged in eight bunches, with each bunch containing over 100 tentacles. The oldest tentacles are often coloured dark red. Fragments of tentacles, left on buoy ropes for example, retain their stinging power.
Great British Marine Animals, by Paul Naylor, Deltor
The Underwater Photographer: Digital and Traditional Techniques, by Martin Edge, Paperback, 424 pages
Dive sites and marine life of the Calf of Man and neighbouring area by Bill Sanderson, Bruce McGregor and Andrew Brierley, Immel Publishing Ltd, Paperback.