The basilisk, king of serpents: from Pliny to the cockerel's egg
Pliny's small crowned serpent, Isidore of Seville, the cockerel's egg hatched by a toad and the arms of Basel: the history of the basilisk in the sources.
The basilisk is one of the most feared fantastic creatures of the European imagination. Unlike the dragon, huge and spectacular, it was imagined as a small animal endowed with a deadly power: killing with its gaze or its breath. Born as a serpent described by ancient naturalists, in the Middle Ages it took on a hybrid appearance and an ever stranger origin, becoming a symbol of sin, of poison and of the evil eye.
Pliny's crowned serpent
The most influential description is found in the eighth book of Pliny the Elder's Natural History. The basilisk, native to Cyrenaica, was said to be no more than twelve fingers long and to bear on its head a white spot like a diadem. With its hiss it would put other snakes to flight, and it would advance holding the front part of its body upright, instead of crawling like its kin.
Pliny adds that the basilisk scorches grass and splits stones with its breath alone, and that its venom is such that it kills even through the spear of the man who strikes it. There was, however, an enemy able to defeat it: the weasel, for «mustelarum virus exitio est», the venom of weasels is fatal to it. The name itself comes from the Greek basiliskos, little king.
The cockerel's egg and the medieval basilisk
Isidore of Seville, in his seventh-century Etymologies, follows Pliny and calls the basilisk regulus, little king, describing it as the king of serpents. In the following centuries, however, the image changed. Medieval bestiaries and encyclopaedias spread the belief that the basilisk was born from an egg laid by an old cockerel and hatched by a toad or a serpent.
From this origin came a new appearance: the basilisk became a hybrid with the head and legs of a cockerel and the tail of a serpent, often called in English the cockatrice. Chaucer, in The Parson's Tale, names it as the basilicok, and in Romanesque and Gothic art it appears carved on capitals, sometimes trampled by Christ according to the Psalm that promises to tread upon the asp and the basilisk.
Mirrors, weasels and cities
The belief in its deadly gaze gave rise to another, that the basilisk could be defeated by a mirror, since on seeing its own reflection it would die. Leonardo da Vinci, in his notes on animals, takes up the traditional reports on the basilisk and on the weasel that fights it, confirming how widespread the legend still was among Renaissance scholars.
Some cities made the basilisk an emblem. In Basel, whose name seemed to recall it, two basilisks support the city's coat of arms and appear on many fountains. In Vienna a legend tells of a basilisk lurking in the well of a house in the centre, still remembered today by a sculpture on the façade of the building known as the Basiliskenhaus.
In the nineteenth century naturalists gave the name basilisk to a genus of Central American lizards able to run on water, and so the ancient monster entered, by a curious irony, scientific nomenclature. Its story shows how a notice handed down by an authority such as Pliny could grow for centuries, gathering details until it became a powerful symbol of the evil that strikes with a glance.