The essential condition in this consists in attacks of unconsciousness, usually accompanied by a discharge of nerve force shown in convulsions, the attack being often preceded by peculiar sensations of some sort known as the aura.

In the most marked forms of the affection heredity plays but little part, owing to the early supervention of imbecility and helplessness, and it is a greater factor in the better classes of society than in the proletariat.

In the better classes, owing to the greater care of the cases and the avoidance of exciting causes of the attacks, the disease is better controlled and rarely advances to the extent that it does among the poor.

The association of epilepsy and alcoholism is especially dangerous, for a slight amount of alcohol may greatly accentuate the disease.

In five hundred and thirty-five children in whose parentage there were sixty-two male and seventy-four female epileptics, twenty-two were born dead, one hundred and ninety-five died from convulsions in infancy, twenty-seven died in infancy from other causes, seventy-eight were epileptics, eleven were insane, thirty-nine were paralyzed, forty-five were hysterical, six had St.Vitus's dance, one hundred and five were ordinarily healthy.
That variations in the nervous system which produce more or less unusual mental peculiarities and which do not take the form of nervous disease are inherited, the most superficial consideration shows.