The writer saw a baby who had a sanguineous discharge from her genitals, for the first time, when she was only five days old. This discharge appeared afterwards regularly every four weeks. At the autopsy of another child one year old, one ovary was so enlarged that it awakened the writer’s curiosity. At the microscopical examination he found a ripe Graafian follicle. The writer also observed erections in a boy eight days old, immediately after the ritual circumcision. In the beginning he attributed these erections to the irritation of the wound. But the erections continued even after the wound was completely healed. The penis had the size of that of a boy four to five years of age. But even where the development of the genital organs conforms with the age of the child, many cases are recorded of children of great precocity. At this period of early childhood there can be naturally no other sex activity except the habit of autoeroticism. The natural curiosity of children leads them to an examination and finally to a titillation of their private organs, often without the aid of any vicious instruction. When the child has thus found that a certain mode of handling these organs is attended with pleasurable sensations, he repeats the action, and the habit is established. Hirschsprung (Berl. Klin. Wochenschr. 1866, No. 38) observed three cases of sexual activity in boys in the earliest childhood. The youngest child was only sixteen months old. Membro mentulato, the boy continued for over an hour to make rocking or wriggling movements, until it would fall back exhausted and bathed in perspiration. Deep sleep terminated the attacks which were repeated daily. Rohleder (Die Masturbation, 3d Edit., p. 58) describes a case of a boy, fifteen months old, qui faciebat motiones voluptarias fricando virilia sua contra mammam matris. The attacks were marked by staring eyes, burning face and oppressed breathing. At the acme of the attack the child would break out in loud sobbing. The paroxysm would last about ten minutes. Thereupon the child would fall asleep. The early aberration of the sexual instinct in childhood is more frequently met with in girls than in boys. Probably because the means for sensual gratificaton at the disposal of the infant girl are more numerous than that of the boy. The mere thigh-crossing of the infant girl will serve the purpose. Townsend reports five cases of stuprum manu in girls under one year of age. One, an infant, eight months old, would cross her right thigh over the left, close her eyes, clench her fists, and after a minute or two there would be complete relaxation, with perspiration and redness of face. This would occur once a week or oftener.