The finding of Drs. Cloutier and Stickler that 3 of 15 children (20%) with idiopathic hypopituitarism and normal intelligence had head circumference measurements of less than -2 S.D. was most interesting. Since my own experience with hypopituitary dwarfs was limited, additional data was obtained from Dr. Thomas Aceto, Jr., of the Children's Hospital of Buffalo, Sew York, and Dr. John D. Crawford of the Children's Service of the Massachusetts General Hospital, Boston, Massachusetts.