Lernaean Hydra that Hera placed the Hydra and crab as constellations in the night sky after Heracles slew him. When the sun is in the sign of Cancer (Latin for "The Crab"), the constellation Hydra has its head nearby. In fact, both constellations derived from the earlier Babylonian signs: Bashmu ("The Venomous Snake") and Alluttu ("The Crayfish"). Primary sources Secondary sources Lernaean Hydra The Lernaean Hydra or Hydra of Lerna (, "Lernaîa Hýdra"), more often known simply as the Hydra, is a serpentine water monster in Greek and Roman mythology. Its lair was the lake of Lerna in the Argolid, which was
Battle of the Lerna Mills Phillips places the number at 250). Prince Demetrios Ypsilantis and several philhellenes volunteered in the defense of the garrison. Protecting Lerna was vital since the mills contained large quantities of grain that supplied food to Nafplion. The mills of Lerna were surrounded by a stone wall that was flanked by a deep pond and a marsh. Moreover, the garrison was supported by two gunboats that were anchored a short distance (or "musket-shot distance") from the shore. Unfortunately, the Greeks did not repair a small break in the stone wall. As a result, a small contingent of Arabs exploited this weakness