Abstract
The author. after a brief resume of earlier work, gives a broad biological discussion of leukemia, with a list of references practically all under 10 yrs. old. In relation to the genesis of leukemia he discusses heredity, maternal influence, sex and sex hormones, thymus, adrenal, nutritional influence, chemical and physical leukemogens, urinary substances stimulating leukopoiesis, leukemoid reactions, biological properties of the leukemic cell, tissue cultures, metabolism of leukemic cells, histogenesis of leukemic cells. In relation to the growth of leukemic cells he takes up genetic and antigenic considerations, hormonal factors, nutritional factors, nursing influence, chemical and physical growth modifiers. Avian leukosis as a virus disease and the somatic mutation theory are treated briefly.