Constellation of Leo - The ruler of Leo is the Sun. The glyph is generally thought to represent the tail of the lion. In ancient Dionysian mysteries it was considered to be a phallus. It can also symbolize the heat or creative energy of the Sun. On entering the sign Leo, the Sun is said to exemplify cosmic splendor. The meaning attached to this seems to be that both the good and bad characteristics associated with Leo are perpetual.