It's covered with a skin. Tell tale signs are the unique hooves and the woman's missing leg. It's just a suggestion. It works for my solution.
I'm certainly not trying to discourage you, but the hooves in the painting appear cloven, while the lamp's are not. If you've got something brewing, keep it going. I think we're all anxious to see someone actually find something!
It may be another reference to English monarchy, monarch butterfly, Queen Victoria, throne chair and king/queen chess piece. Animal's hooves are sheep like. It may be a sheep in sheep's clothing. English members know what I'm talking about; Churchill’s memorable phrase, “a sheep in sheep’s clothing”