The Blue Sea Slug (Glaucus atlanticus)
is a nudibranch, class Gastropoda, phylum Mollusca. This conspicuous
group of molluscs are usually very brightly coloured and can range
in size from less than one eigth of an inch to over a foot in
length. They lack a shell and their bodies are always bilaterally
symmetrical. The head sports a pair of antennae-like rhinopores.
Most have gills on the posterior part of the body and some can
retract their gills into a branchial pocket. The dorsal surface
of the nudibranch often has cerata, digitate or club-like projections
of tissue that can often be extremely colourful. These cerata
are used in respiration, defense and digestion. Glaucus
is a voracious predator of the Portuguese
Man-O-War (Physalia physalis), the By-The-Wind-Sailor
(Velella velella) and the Blue
Sea Star (Porpita porpita). When feeding upon these
cnidarians it transfers its prey's stinging cells, nematocysts,
into its own cerata and then utilizes them for its own defence.
Glaucus is found floating on the sea surface where it maintains
bouyancy by swallowing air.
meaning of the name 'Glaucus'
Glaucus was a character in Greek mythology and
it means the "colour of the sea".
Glaucus was a fisherman. One day he had
drawn his nets to land, and had taken a great many fishes of various
kinds. So he emptied his net, and proceeded to sort the fishes
on the grass. All of sudden, the fishes, which had been laid out
on the grass, began to revive and move their fins as if they were
in water; and while he looked on astonished, they one and all
moved off to the water, plunged in, and swam away. He did not
know what to make of it, whether some god had done it or some
secret power in the herbage. "What herb has such power?" he exclaimed;
and gathering some of it, he tasted it. Scarce had the juices
of the plant reached his palate when he found himself agitated
with a longing desire for water. He could no longer restrain himself,
but bidding farewell to the earth, he plunged into the stream.
The gods of the water received him graciously, and admitted him
to the honor of their society. He lost all sense of his former
nature and consciousness. When he recovered, he found himself
changed in form and mind. His hair was sea-green, and trailed
behind on the water. He was endowed with the gift of prophecy
and instructed Apollo in the art of soothsaying.
This story is from http://www.myth.com/mythopoeia/
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