The basilisk, or cockatrice, was a serpent so horrible that it killed with a glance. Pliny the Elder described it simply as a snake with a small golden crown. By the Middle Ages it had become a snake with the head of a cock or sometimes a human head. It was born of a spherical egg, laid during the days of Sirius, the Dog Star, by a 7-year-old cock. The egg was then hatched by a toad. The sight of a basilisk was so dreadful that if the creature saw its own reflection in a mirror it would supposedly die of fright. The only way then to kill it was to hold a mirror before it and avoid looking at it directly. The original of the basilisk could have been a horned adder or the hooded cobra of India.