=I´o=, a daughter of Inachus, was a priestess of Juno at Argos. Juno changed her into a beautiful heifer, and eventually restored her to her own form. She was greatly persecuted by Juno. She married Telegonus, king of Egypt, or Osiris, according to others, and treated her subjects with such kindness that after death she received divine honors, and was worshiped under the name of Isis. =I´olas= or =Iola´us=. A son of Iphiclus, king of Thessaly, who assisted Hercules in conquering the Hydra; he burnt with a hot iron the place where the monster's heads had been cut off to prevent their re-growth. =Iph´iclus.= A son of Amphitryon and Alcmena, twin brother of Hercules. As the children were cradled together, Juno, jealous of Hercules, sent two large serpents to destroy him. At the sight of the snakes Iphiclus showed great alarm, but Hercules seized them, one in each hand, and squeezed them to death. =Iphic´rates.= A celebrated general of Athens, who, though son of a shoemaker, rose to the highest offices in the state. He made war against the Thracians, and assisted the Persian king against Egypt. =Iphigeni´a.= A daughter of Agamemnon and Clytemnestra. When the Greeks, going to the Trojan war, were detained at Aulis by contrary winds, they were informed by a soothsayer that to appease the gods they must sacrifice Iphigenia to Diana. As the fatal knife was about to be plunged into her, Iphigenia suddenly disappeared, and a goat of great beauty was found in the place where she had stood ready for the sacrifice. =Iph´itus.= A son of Eurytus, king of OEchalia. When his father had promised his daughter Iole to any one who could excel him or his sons in drawing the bow, Hercules accepted the challenge and was victorious. Eurytus, however, refused to fulfill the compact by giving his daughter to the conqueror. Afterwards some oxen were stolen from Eurytus, and Iphitus was sent in quest of them. In his search he met Hercules, who aided him in seeking the lost animals, but on recollecting the faithlessness of Eurytus he killed Iphitus. =Irenæ´us.= A native of Greece, disciple of Polycarp, and bishop of Lyons. He wrote on different subjects, and suffered martyrdom A.D. 202. =I´ris.= One of the Oceanides, messenger of the gods, and more particularly of Juno. Her office was to cut the thread which seemed to detain the soul of those who were expiring. She is the same as the rainbow. =I´sis.= A celebrated deity of the Egyptians, daughter of Saturn and Rhea, according to Diodorus of Sicily. Some suppose her to be the same as Io, who was changed into a cow, and restored to her human form in Egypt, where she taught agriculture, and governed the people with mildness and equity, for which she received divine honors after her death.