sword or his famed club, Heracles engaged the Hydra in combat. Ruck and Staples (1994: 170) note that the chthonic creature's reaction was botanical in nature: upon cutting off each of its heads, Heracles observed that the beast promptly re-grew each decapitated head, rendering every slash and cleaving blow futile. Additionally, one of the Hydra's heads - the middle one - was immortal. The details of the struggle are explicit in the Bibliotheca (2.5.2): realizing that he could not defeat the Hydra in this way, Heracles called on his nephew Iolaus for help. Iolaus then came upon the idea (possibly inspired by Athena) of using a firebrand to scorch the neck stumps after each decapitation. Working in tandem, Heracles cut off each head and Iolaus cauterized the open stumps. Seeing that Heracles was winning the struggle, Hera sent a giant crab to distract him; however, this turned out to be in vain, as he promptly crushed it under his mighty foot. Lastly, having weakened the beast considerably, Heracles cut off the Hydra's one immortal head with a golden sword given to him by Athena. It is said that Heracles placed the immortal head under a great rock on the sacred way between Lerna and Elaius to keep the beast from enacting further harm (Kerenyi 1959:144), and once this was done, he dipped his arrows in the Hydra's poisonous blood. An alternative version of this myth relates that after cutting off one of the Hydra's heads, Heracles dipped his sword in the gaping wound and used its venom to cauterize each subsequent stump so that it could not grow back. Hera, upset that Heracles had slain the beast she raised to kill him, is said to have placed it in the dark blue vault of the sky as the constellation Hydra. She then turned the crab into the constellation Cancer. Later, Heracles used an arrow dipped in the Hydra's poisonous blood to kill the centaur Nessus; and Nessus's tainted blood was applied to the Tunic of Nessus, by which the centaur had his posthumous revenge. Both Strabo and Pausanias report that the stench of the river Anigrus in Elis, making all the fish of the river inedible, was reputed to be due to the Hydra's venom, washed from the arrows Heracles used on the centaur. Third: Ceryneian Hind Angered by Heracles' success against the Nemean Lion and the Lernaean Hydra, Eurystheus