Authors tell the fable that Ceres was Proserpina's mother, and that Proserpina while playing one day was kidnapped by Pluto. Her mother searched for her with lighted torches; and it was decreed by Jupiter that the mother should have her daughter for fifteen days in the month, but Pluto for the rest, the other fifteen. This is nothing but that the name Ceres is used to mean the earth, called Ceres on analogy with "crees" ('you may create'), for all things are created from her. By Proserpina is meant the moon, and her name is on analogy with "prope serpens" ('creeping near'), for she is moved nearer to the earth than the other planets. She is called earth's daughter, because her substance has more of earth in it than of the other elements. By Pluto is meant the shadow that sometimes obstructs the moon.