Cases of too frequent nocturnal emissions accompanied by languor and headache are usually caused by irritability or lack of tonicity of the sexual apparatus, particularly of the seminal vesicles and the ducts. This irritability and loss of tone is not infrequently caused by masturbation, though it may also be caused by excessive sexual intercourse, making itself manifest, of course, in either case, on cessation of the habit of masturbation or the excessive sexual intercourse. Another cause of too frequent nocturnal emissions and one wholly separate from any abuse of the sexual function is irritability and mechanical irritation of the sexual apparatus--perhaps especially the membranous and prostatic portion of the urethra--caused by the presence of an excessive amount of oxalates in the urine. Oxalates occur in the urine in sharp angular crystals and would seem to be in a high degree irritating to the tender mucous membrane of the upper part of the urethra. The almost invariable presence of these crystals in excess in those cases that have not been accounted for by abuse of the sexual function leads one to adopt the plausible theory that the crystals are the cause of the irritability. However, we must not lose sight of the fact that these crystals may be simply an accompaniment of the too frequent emissions, and that the presence of oxalates in the urine may be caused by some disturbance in the nutritive processes that go on in the body, which disturbance causes not only the irritability of the sexual apparatus, but also the presence of the crystals. When the seminal vesicles are much distended it occurs not infrequently that the passage of a hard mass of fecal material through the rectum will, by simple mechanical pressure on the seminal vesicles, force out a few drops, perhaps as much as a teaspoonful, of the contents of the vesicles. This would be called an _involuntary emission_, but the liquid passed out must not be looked upon as semen. It is simply the secretion of the seminal vesicles, and in losing it, one is not losing a vital fluid or a fluid, any portion of which would be reabsorbed; he is simply losing a fluid which would, in the natural course of events, have passed away within the next few days as a nocturnal emission.