There is a very intimate connection between the vesical and the sexual spheres, as I have elsewhere pointed out (see e.g. in the third volume of these _Studies_, "Analysis of the Sexual Impulse"). This connection is psychic as well as organic. Both in men and women, a full bladder tends to develop erotic dreams. (See e.g. K.A. Scherner, _Das Leben des Traums_, 1861, pp. 187 et seq.; Spitta also points out the connection between vesical and erotic dreams, _Die Schlaf und Traumzustände_, 2d ed., 1882, pp. 250 et seq.) Raymond and Janet state (_Les Obscessions_, vol. ii, p. 135) that nocturnal incontinence of urine, accompanied by dreams of urination, may be replaced at puberty by masturbation. In the reverse direction, Freud believes (_Monatsschrift für Psychiatrie_, Bd. XVIII, p. 433) that masturbation plays a large part in causing the bed-wetting of children who have passed the age when that usually ceases, and he even finds that children are themselves aware of the connection. The diagnostic value of sexual dreams, as an indication of the sexual nature of the subject when awake, has been emphasized by various writers. (E.g., Moll, _Die Konträre Sexualempfindung_, Ch. IX; Näcke, "Der Traum als feinstes Reagens für die Art des sexuellen Empfindens," _Monatsschrift für Kriminalpsychologie_, 1905, p. 500.) Sexual dreams tend to reproduce, and even to accentuate, those characteristics which make the strongest sexual appeal to the subject when awake.