that sexual excitement during sleep is more fatiguing than in the waking state, though this is not an invariable rule, and it is sometimes found to be refreshing.  In a similar way, Eulenburg (Sexuale Neuropathie, p. 55) states that nocturnal emissions are no more normal than coughing or vomiting.

Nocturnal emissions are usually, though not invariably, accompanied by dreams of a voluptuous character in which the dreamer becomes conscious in a more or less fantastic manner of the more or less intimate presence or contact of a person of the opposite sex.  It would seem, as a general rule, that the more vivid and voluptuous the dream, the greater is the physical excitement and the greater also the relief experienced on awakening.  Sometimes the erotic dream occurs without any emission, and not infrequently the emission takes place after the dreamer has awakened.

The widest and most comprehensive investigation of erotic dreams is that carried out by Gualino, in northern Italy, and based on inquiries among 100 normal men—­doctors, teachers, lawyers, etc.—­who had all had experience of the phenomenon. (L.  Gualino, “Il Sogno Erotico nell’ Uomo Normale,” Rivista di Psicologia, Jan.-Feb., 1907.) Gualino shows that erotic dreams, with emissions (whether or not seminal), began somewhat earlier than the period of physical development as ascertained by Marro for youths of the same part of northern Italy.  Gualino found that all his cases had had erotic dreams at the age of seventeen; Marro found 8 per cent, of youths still sexually undeveloped at that age, and while sexual development began at thirteen years, erotic dreams began at twelve.  Their appearance was preceded, in most cases for some months, by erections.  In 37 per cent, of the cases there had been no actual sexual experiences (either masturbation or intercourse); in 23 per cent, there had been masturbation; in the rest, some form of sexual contact.  The dreams are mainly visual, tactual elements coming second, and the dramatis persona is either an unknown woman (27 per cent, cases), or only known by sight (56 per cent.), and in the majority is, at all events in the beginning, an ugly or fantastic figure, becoming more attractive later in life, but never identical with the woman loved during waking life.  This, as Gualino points out, accords with the general tendency for the emotions of the day to be latent in sleep.  Masturbation only formed the subject of the dream in four cases.  The emotional state in the pubertal stage, apart from pleasure, was anxiety (37 per cent.), desire (17 per cent.), fear (14 per cent.).  In the adult stage, anxiety and fear receded to 7 per cent, and 6 per cent., respectively.  Thirty-three of the subjects, as a result of sexual or general disturbances, had had nocturnal emissions without dreams; these were always found exhausting.  Normally (in more than 90 per cent.) erotic dreams are the most vivid of all dreams.  In no case