all this cannot be attributed to alcohol alone. There is first to be considered a probable variation in the nervous system which is expressed in the alcoholic habit; second, the environment consisting in poverty, bad associates, etc., which the alcoholic habit brings; third, the alcohol alone. That defective inheritance so frequently takes the form of alcoholism is largely due to the environment. There has never been the opportunity to study on a large scale the effect of the complete deprivation of alcohol from a people living in the environment of modern civilization. There is a possibility, and even probability, that the defective nervous organization which predisposes to alcoholism would seek satisfaction in the use of some other sedative drug. So complex are all the interrelations of the social system that it would be possible to regard alcohol as an agent useful in removing the defective, were it not for its long-enduring action and its effects on the descendants, procreation not being affected by its use. Diseases of the nervous system are particularly apt to affect the offspring, and often the inherited condition repeats that of the parents. This is due to the fact that most of the nervous diseases depend both upon intrinsic factors which consist in some defective condition of the nervous system representing a variation, and extrinsic factors due to environment or occupation which make the basal condition operative. The definite relation between alcoholism and insanity is due to alcohol acting not as an intrinsic but an extrinsic factor, bringing into effectiveness the hereditary weakness of the nervous system. The influence of heredity in producing insanity is variously estimated at from twenty-six per cent to sixty per cent of all cases. This great difference in the estimation of the hereditary influence is due to the personal equation of the statistician, and the care with which other factors are eliminated. In the more severe form of the hereditary degeneration the same pathological conditions are repeated in the descendants. In certain cases the severity of the condition increases from generation to generation. According to Morel there may be merely what is recognized as a nervous temperament often associated with moral depravity and various excesses in the first generation; in the second, severe neuroses, a tendency to apoplexy and alcoholism; in the third, psychic disturbances, suicidal tendencies and intellectual incapacity; and in the fourth, congenital idiocy, malformations and arrests of development. There are some very definite data with regard to inheritance in the nervous disease known as epilepsy. 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