the heart, with a tendency to pulmonary congestion, and attacks of “cardiac asthma.”  His wife, a lady of great intelligence, kept notes of her husband’s condition,[122] and at last observed that there was a certain periodicity in the occurrence of the exacerbations.  The periods were not quite regular, but show a curious tendency to recur at about thirty days’ interval, a few days before the end of every month; it was during one of these attacks that he finally died.  There was also a tendency to minor attacks about ten days after the major attacks.  It is noteworthy that the subject showed a tendency to periodicity when in health, and once remarked laughingly before his illness:  “I am just like a woman, always most excitable at a particular time of the month.”

Periodicity has been noted in various disorders of nervous character.  Periodic insanity has long been known and studied (see, e.g., Pilcz, Die periodischen Geistesstoerungen, 1901); it is much commoner in women than in men.  Periodicity has been observed in stammering (a six-weekly period in one case), and notably in hemicrania or migraine, by Harry Campbell, Osler, etc.  (The periodicity of a case of hemicrania has been studied in detail by D. Fraser Harris, Edinburgh Medical Journal, July, 1902.) But the cycle in these cases is not always, or even usually, of a menstrual type.

It is now possible to turn to an investigation which, although of very limited extent, serves to place the question of a male menstrual cycle for the first time on a sound basis.  If there is such a cycle analogous to menstruation in women, it must be a recurring period of nervous erethism, and it must be demonstrably accompanied by greater sexual activity.  In the American Journal of Psychology for 1888, Mr. Julius Nelson, afterward Professor of Biology at the Rutgers College of Agriculture, New Brunswick, published a study of dreams in which he recorded the results of detailed observations of his dreams, and also of seminal emissions during sleep (by him termed “gonekbole” or “ecbole"), during a period of something over two years.  Mr. Nelson found that both dreams and ecboles fell into a physiological cycle of 28 days.  The climax of maximum dreaming (as determined by the number of words in the dream record) and the climax of maximum ecbole fell at the same point of the cycle, the ecbolic climax being more distinctly marked than the dream climax.

The question of cyclic physiological changes is considerably complicated by our uncertainty regarding the precise length of the cycle we may expect to find.  Nelson finds a 28-day cycle satisfactory.  Perry-Coste, as we shall see, accepts a strictly lunar cycle of 291/2 days.  Fliess has argued that in both women and men, many physiological facts fall into a cycle of 23 days, which he calls male, the 28-day cycle being female. (W.  Fliess, Die Beziehungen zwischen Nase und weiblichen Geschlechts-Organen,