The long constellation Hydra lies south of Cancer, Leo, Crater, Corvus, Virgo, and Libra. It was also called Asina, Coluber, Anguis, Sublimatus, etc. In the Greek mythology it was supposed to represent the Lernæan serpent killed by Hercules. According to Ovid, who fixed its acronycal rising for February 14, it had a common origin with Corvus and Crater. Apollo, wishing to sacrifice to Jupiter, sent the Crow with a cup to fetch water. On his way to the well the Crow stopped at a fig tree and waited for the fruit to ripen! Afterwards, to excuse his delay, he said that a serpent had prevented him from drawing the water. But Apollo, to punish the Crow for his deception, changed his plumage from white to black, and ordered the serpent to prevent the Crow from drinking.[442] Hydra was called by Al-Sufi _al-schudja_, "the Serpent, or Hydra." He says that "it contains twenty-five stars in the figure and two 'outside', and its head is to the south of the southern scale of the Balance" (α Libræ). But this is clearly a mistake (one of the very few errors to be found in Al-Sufi's work), for he goes on to say that the head is composed of four stars forming a figure like the head of a horse, and he adds, "This head is in the middle between _al-shira al-gumaisa_ [Procyon] and _Kalb al-asad_ [Regulus] the Heart, inclining from these two stars a little to the south." This clearly indicates the stars δ, ε, η, and σ Hydræ which, with ζ Hydræ, have always been considered as forming the Hydra's head. These stars lie south of α and β Cancri, not south of Libra as Al-Sufi says (doubtless by a slip of the pen).