Nocturnal pollutions are to be regarded as pathological when they occur in married or single men who indulge in regular intercourse; when they are followed by backache, headache, enfeeblement of the functional powers of the brain, mental depression, and bodily or mental lassitude; when they take place without erections or dreams; when they accompany or follow acute or chronic diseases; when they coexist with diurnal pollutions or spermorrhagia; and, finally, when they are complicated by one of the varieties of impotence, which may be the only indication that the emissions are abnormal or one of the effects of impairment of the functions of the genital nervous centres. The associated symptoms of myelasthenia and cerebrasthenia vary very much in degree in men of apparently the same amount of vigor and tolerance, and in whom the pollutions occur with equal frequency, or they may even be absent altogether. 2. Diurnal Pollutions.--Ejaculation of semen during the day is fortunately of comparatively infrequent occurrence, since it indicates a more serious condition than do losses of seminal fluid occurring when the patient is asleep, the genital organs and the centres which preside over them being highly impressible or in a state of irritable weakness. In what may be regarded as the lesser form of the affection the ejaculation is due to slight peripheral irritation, induced, for example, by friction of the clothing, crossing of the legs repeated several times, horseback exercise, driving over rough streets, riding in railway-cars, or even shaving, combing the hair, or shampooing the head; while in the more aggravated variety an emission is induced by psychical irritation, such as reading libidinous books, the sight of indecent pictures, dwelling upon sexual ideas, or the mere sight of a female. In the former of these varieties there is a fair erection, but the sensibility is blunted; in the latter the erection is flabby or the penis is flaccid and there is little if any pleasure. 3. Spermorrhagia.--In the third phase of the affection, which is still more uncommon than the second variety, there is a continuous passive loss of semen, without erection or sensation--a condition which depends upon paralysis and dilatation of the orifices of the ejaculatory ducts, and which is most conspicuous during the acts of micturition and defecation. The existence of spermatorrhoea, in the restricted sense of the term, is denied by some authors, but I have myself met with it in five instances, and typical cases have been recorded by other modern writers.