DIAGNOSIS.--The microscope affords the only positive mode of determining whether the fluid which is discharged from the urethra during {142} pollutions, or constantly moistens that canal in spermorrhagia, or is expelled at stool or with the urine, or is brought away by the bulb of the explorer, is seminal in its character. Should spermatozoids be detected, there can be no doubt as to its true nature, but their absence is not an evidence that the case is not one of spermatic incontinence, since in the condition known as azoospermatorrhoea the exhausted sexual apparatus furnishes a thin, transparent, watery fluid which may be entirely devoid of fertilizing elements, and contains cylinder epithelial cells, epithelium which has undergone fatty or colloid degeneration, a few lymph-corpuscles, an abundance of fatty detritus, and a few small shining bodies which are the remains of the badly-evolved spermatozoids. Under these circumstances, the history of the case, the fact that the subject is or was a masturbator, and the associated nervous symptoms are aids in forming a diagnosis; and this is especially true of cases in which a fluid is expressed at stool, and which in the majority of instances is the altered secretion of the prostate. Under the microscope the thin, more or less milky prostatic fluid will be found to contain cylinder epithelium, numberless colorless and refracting granules of lecithin, and minute yellowish concentric amyloid concretions; and, after it has slowly dried upon the slide, crystals of phosphate of magnesium or of ammonio-magnesian phosphate will make their appearance. Should a microscopical examination be impracticable, we may assume that the discharge which occurs during defecation in the subjects of too frequent nocturnal pollutions is an evidence of coexisting prostatorrhoea; while we may frame the rule that the flocculent sediment contained in the urine and the discharge at stool of persons suffering from both nocturnal and diurnal pollutions, and a slight continued discharge from the urethra represents semen. In the last event we may moreover assume, especially if the patient be impotent, that the orifices of the ejaculatory ducts are relaxed.