IN Science and Society of June-September 1937. there appears an article on "The Scientific Basis of Birth Control" by Dr. C. V. Drysdale, president of the Malthusian League. The author remarks that the true, present-day application of the Malthusian doctrine may best be understood by reference to the affairs of an ordinary married couple. "The average young man marries when his income is sufficient to support a wife and perhaps one child, and, if that income were fixed, every additional child would mean a lowering of the family standard of existence." But, in many occupations, salaries rise with age and service, and if additional children come when there has been a sufficient rise in income, no lowering of the standard need take place. "This is the population problem as it confronts almost every middle-class couple." If children arrive at a greater rate than can be allowed for by increases of salary, then such a family is "over-populated". It amounts to this, that, in general, in civilized countries, birth-control has assisted in the preservation of the amenities and standards of living. Another aspect of birth-control is, of course, its application to what is called negative eugenics, that is, the avoidance of parenthood by persons afflicted with transmissible disease or defect. Dr. Drysdale looks forward to a future in which a planned social economy shall ensure general early marriage with reasonable family limitation. But it will be necessary to arrange that the limitation does not go too far, and the question is: How?