Lamien

Lamia
The ancient Greeks believed that the Lamia was a vampire who stole little children to drink their blood. She was portrayed as a snake-like creature with a female head and breasts. Usually female, but sometimes referred to as a male or a hermaphrodite. According to legend, she was once a Libyan queen (or princess) who fell in love with Zeus. Zeus' jealous wife Hera deformed her into a monster and murdered their offspring.
http://www.pantheon.org/articles/l/lamia.html

Lamia
Although lamia were generally believed to have been demons, associated with succubus and with Lilith, they were also synonymous to some with witches. Lamia witches could either look like women, but with horse's hoofs, or they could be a "scaly, four-legged creature, with hoofs behind and paws in front, with a woman's face, a hermaphrodite with a man's organ and woman's breasts"
http://www.bigfoot.com/~ShanMonster/witch/traits/lamia.html

Pre-Raphaelite Sorceresses - Lamia
The original story of Lamia comes from Greek mythology. Her children were murdered by a jealous rival, and she took revenge by murdering the children of others. Lamia's cruelty turned her face into a terrifying mask, and later she seduced young men and killed them in their sleep by sucking their blood. Her name derives from 'lamyros', meaning gluttony, and in this context implied female lechery.
http://www.webmagick.co.uk/prcoll/sorcery/sorcery13.html