CNIDARIA (COELENTERATES)- THE JELLYFISH, SEA ANEMONES ET AL.

BUNODOSOMA

The teflon anemone, Bunodosoma californica

The Phylum Cnidaria consists of radially symmetrical animals and the least complex of the animals that share a common muticellular ancestor. All are carniverous and poison their prey with darts from specialized cells called nematocysts. The phylum includes, jelly fish, hydrozoans (including the man-of-war), sea anemones, and corals. Many have symbotic photosynthetic microscopic organisms in their flesh.
Although the sting of most cnidarians is harmless to humans, that is not true of the group of hydrozoans called the "man-of-war", such as the Pacific man of war Physalia utriculus which superficially resembles a jellyfish. However a jellyfish is a single polyp while a man of war is a colony of individuals specialized to do different tasks much like tissues.

The reaction of a human to the sting of a man-of-war varies from local pain that passes quickly, to severe reactions that can be fatal. Occasionally they are washed on shore my the millions. Otherwise they are quite rare near shore.

PACIFIC