If we speak of predisposing causes, some reference should be made to the influence of the physiological landmarks which are of so much significance in the life of the individual in more ways than one—puberty, adolescence, the climacterium and the senium. A no less noteworthy factor in the female sex is the puerperium. These periods of life are of tremendous importance in the development of the psychoses. It is customary to speak of age, sex, race, civil condition, degree of education, climate, civilization, etc., as factors in the production of mental diseases. Not much is to be said on these questions, nor are they closely related to the subject. On January 1, 1920, there were 232,680 patients in the hospitals for mental diseases in the United States. Fifty-two per cent of these were men and forty-eight per cent women. This represents about the difference that has been shown for many years. The reduction in alcoholic psychoses may affect this ultimately. The striking exceptions to this ratio are Massachusetts and New York, where the number of women has slightly exceeded the men for a number of years. The admission rate for men is, however, slightly higher than that for women in both of those states. Less than one-half of one per cent of the patients admitted to the New York hospitals are under fifteen years of age. In that state approximately five per cent have been between fifteen and nineteen years old. In Massachusetts the percentage of persons admitted who were under twenty years of age has averaged 8.5 quite consistently for some time. The admission rate, for twenty to twenty-five, twenty-five to thirty, thirty to thirty-five and thirty-five to forty years of age in Massachusetts and New York has averaged from ten to eleven per cent for each of those periods for several years. From the age of forty to fifty the admission rate is about 8.5 per cent, and from fifty to sixty between five and six per cent. Nine per cent of the admissions in Massachusetts and eight per cent in New York are seventy years of age or over. The statistics on race, birthplace and the psychoses of the various races are shown in detail in the chapter on Immigration. The admission rate in New York is almost exactly the same for the married and the unmarried, the former constituting about thirty-nine per cent and the latter forty. In Massachusetts the single first admissions amount to about forty-three per cent and the married approximately forty per cent. Throughout the country generally the unmarried slightly predominate. The percentage of widowed in Massachusetts and New York varies from thirteen to fourteen per cent. The divorced constitute only about one per cent of all admissions. As to education, it may be said that about nine per cent of all first admissions are illiterate, from fifteen to twenty per cent can read and write only, about sixty per cent have had a high school and two per cent a college education.