boring appeared at a time which preceded the infantile onanism localized in the genitals. This fact is of significance in so far as this boring differs thereby from a similar later practice which appeared after the genital onanism. The later bad habits represent, as a rule, a substitution for repressed genital masturbation, or for an attempt in this direction. As such these habits (finger-sucking, biting the nails, picking at things, boring into the ears and nose, etc.) may persist far into adult life as regular symptoms of a repressed amount of libido.
As has already been shown above, the libido in youthful individuals at first manifests itself in the nutritional zone, when food is taken in the act of suckling with rhythmic movements and with every sign of satisfaction. With the growth of the individual and the development of his organs the libido creates for itself new avenues to supply its need of activity and satisfaction. The primary model of rhythmic activity, producing pleasure and satisfaction, must now be transferred to the zone of other functions, with sexuality as its final goal. A considerable part of the "hunger libido" is transferred into the "sexual libido." This transition does not take place suddenly at the time of puberty, as is generally supposed, but very gradually in the course of the greater part of childhood. The libido can free itself only with difficulty and very slowly from that which is peculiar to the function of nutrition, in order to enter into the peculiarity of the sexual function. Two periods are to be distinguished in this state of transition, so far as I can judge—the epoch of suckling and the epoch of the displaced rhythmic activity.
