The phenomena which we are at present investigating find a counterpart in the story of the Medusa petrifying those who looked upon her, in the legend of the basilisk that could kill with a look, and of the serpent that caused death to mortals by hissing. One of these legends holds its ground to the present day, namely, that the breath of serpents is poisonous, and that they have a magic power in their look which attracts and fascinates their prey. But this is not correct, these also are cataplectic phenomena. When defenceless birds see a serpent approach their nest, they begin to scream and flap their wings, as though trying to draw its attention upon themselves, and so to save their young. Blinded by love and emotion they rush upon the enemy and then remain as though paralysed, scarcely moving wings or claws, or else they let themselves fall into the jaws of the serpent and are devoured. IV It is well-known that fear may result in sudden death. Bichat maintained that it was essentially paralysis of the heart which causes death in strong emotions. 'The forces of the circulatory system,’ he says, 'are worked up to such a pitch that they cannot recover from the sudden exhaustion, and death ensues.’ Old people in particular are liable to succumb to strong mental emotions. This fact stands in apparent contradiction to that of their sensibility, which is generally much less acute than in youth, but it is the weakness of their nervous system which destroys the balance. Often after great catastrophes parents succumb in consequence of the death of their children, while the brothers and sisters offer more resistance to grief. Marcello Donato and Paolo Giovio relate that at the siege of Buda, in the war against the Turks, there was a youth whose valour excited the admiration of all. Unhappily he fell a victim to the repeated attacks of the besiegers. When the battle was over, the leaders hastened to learn who the hero was. Scarcely had the visor been taken from his face than Raischach of Swabia recognised his son. He stood motionless, his eyes fixed upon his son, then fell dead to the ground without uttering a word. As a proof that weakness more easily causes death in emotion, I here mention an experiment of Johannes Müller. He destroyed the liver of some frogs, thus rendering them very weak and excitable. The slightest stimuli produced contractions in them, but they did not move if left in peace, and even lived for a long time. Those he took into his hand were immediately attacked by tetanus and died in a few seconds.