According to myth, the beautiful creatures of the ocean called Mermaids often took human lovers, and the male offspring that came of these unions became Otherworldly children, who would return to the ocean as Mermen.
You may have wondered why little is mentioned of Mermen, compared to Mermaids. Perhaps as the sailors of the past were always men, away from other women for long periods of time, a beautiful woman would be more pleasing to their eyes, than a handsome man.
This was of course to the advantage of these beautiful, yet unpredictable creatures.
Mermaids possess a woman’s body from above the waist, and a fish’s tail below. The classical image of the Mermaid is of her sitting on a rock, combing her hair, singing; and luring seafarers to their doom with her enchanted voice.
Mermaids have usually been portrayed as evil because of their association with Sirens; evil temptresses in Greek mythology. However, Mermaids were also said to give treasures to sailors they favoured, and would warn them about the approach of violent storms. All in all, they were considered to be creatures of whim.
Some Mermaids turned their backs on their natural ocean homes, and choose to take human lovers. They sacrificed their beautiful fish tails and assumed human form, in order to live on the land, for the sake of love with a male human. More often than not however, they would eventually return to the sea.
Mermen were depicted as having webbed fingers and toes, and in Greek mythology they were said to have green beards and hair, and were able to breathe under the water like fish. Rather than stay with their parents on land, they would invariably return to their real mother, the ocean, where they would cause violent storms, and sink passing ships.
As a sailor in the ancient world, dependent upon safe passage across the perilous ocean, it was vital to have the gods on your side. As well as painting eyes on the prows of the ships so they could ‘see’ where they were going, amulets were also carried, and offerings made to the watery beings to encourage them not to sink the ship or kill the sailors.
• Animals were sacrificed at the beginnings of voyages and offered to the aquatic world; in particular, horses, as they were sacred to the Greek god the sea, Poseidon.
• Crystals were carried to protect sailors; such as agate, garnet, aquamarine and quartz.
• Pieces of coral and jewels were attached to the prow for protection, so that Mermaids could take them as jewellery instead of luring the sailors.
Harry Potter's Magical Creatures ~ Myths and Legends - http://www.amazon.com/dp/B004IE9YBA