B has had no serious illnesses or accidents; her health history appears normal and her physical condition at the present time is excellent. Furthermore, she seems unusually well balanced from the standpoint of mental hygiene. B exhibits regularity in habits, sleeps soundly, seldom reports dreams, displays no unusual fears, and adapts herself quickly and successfully to the demands of her child-group. B's parents appear distinctly above the average both in intelligence and in academic training. The mother finished a two-year normal course and taught for a number of years in a metropolitan school system. The father is an electrical engineer, a graduate of Case College of Applied Science; he has pursued graduate studies at Cornell University, and has done some college teaching. At present he is a practicing electrical engineer. . . . Her maternal great-grandfather (who is still active and robust at age 82) was private secretary to each of four executives of a large railroad system. . . . Her paternal grandfather was an inventor and manufacturer of polishes and waxes. . . . The mother reports B to be of pure Negro stock. There is no record of any white ancestors on either the maternal or paternal side. B has not much ability or interest in music. Her favorite subject is science, and chemistry attracts her to the extent that she wishes to become a chemist. _Child R_. In 1936, Zorbaugh and Boardman (38) described a boy, R, of IQ 204 (S-B). They mention also three other children of IQ above 180, tested at New York University's Clinic for the Social Adjustment of the Gifted, but R is the only one described. R was brought to the Clinic when he was 8 years old, and at that time he had on the Stanford-Binet an IQ of 204. His father, an engineer, is a well-known writer in the scientific field. His mother holds a doctor's degree in physical chemistry from a foreign university. Neither the father nor the mother has been tested, but they are both persons of very unusual mental ability. R's two younger brothers are also of very superior mentality. The family is of Jewish origin and both the father and the mother were born in a foreign country.