sentences:  The name has a largely obsolete variant, Japetus ,
  with an adjectival form "Japetian".These occur because there was no distinction between the letters and in Latin, and authors rendered them differently.When first discovered, Iapetus was among four Saturnian moons labelled the "Sidera Lodoicea" by their discoverer Giovanni Cassini after King Louis XIV (the other three were Tethys, Dione and Rhea).