I have chosen this title as inferring as little as possible any relation other than that of time between the states of disorder. Night follows day, but is not caused by it, and, as we shall see, in some cases one form of nervous disorder is followed by another form of disorder, both having probably a similar cause, but not the one depending on the other as its cause. It is only necessary to say that I use the term neurosis in a very general way, thereby meaning any well recognized disturbance of the nervous system which might be considered due to direct inheritance, or might itself start a morbid nervous series.