108 GREEK AND ROMAN MYTHOLOGY Cithaeron, where he killed a powerful lion. When his father had fallen in battle against the Orchomenians, Creon, the last of the Sparti, became king of Thebes, and to Hercules was given his daughter Megara as a wife. In a fit of madness, which Hera decreed upon him, he killed his three children with bow and arrows. On his recovery he was compelled in expiation of his crime to enter the service of Eurystheus, who laid upon him a series of difficult labors, the order of which varies in different versions of the myth. The collection of legends describing these labors forms the connecting link between the Theban-Boeotian and the Argive-Dorian Hercules myths. The latter of these two series of myths seems to embrace the labors in their oldest form. 138. According to this version Hercules had his abode in Tiryns, south of Mycenae, to which, indeed, the story of his birth points. (1) He fought at Tiryns, as he had done on Cithaeron, with a powerful lion, which lived on Mount Apesas, between Nemea and Mycenae. After this he wore the skin of this lion, flung over the upper part of his body, as a characteristic dress. (2) Accom- panied by his friend and charioteer, lolaus, he went against the Hydra, a nine-headed water serpent in the marshy springs of Lerna, south of Argos. In place of every one of the monster's heads that was struck off two new ones grew, until lolaus set the neighboring woods on fire and burned out the wounds (i.e. dried up the springs). The last immortal head Hercules covered with a block of stone. Then he moistened the tips of his arrows with the venom of the monster. 139. (3) From Mount Ery man thus in Arcadia, from whose snow-covered summit a wild mountain stream of