well
suppose that the organism became adjusted to the rhythms of its
environment by a series of congenital variations. Or it might be held, on
the basis of Weismann's doctrine, that the germ-plasm has been directly
modified by the environment.

[77] Thus, the Papuans, in some districts, believe that the first
menstruation is due to an actual connection, during sleep, with the moon
in the shape of a man, the girl dreaming that a real man is embracing her.
(_Reports Cambridge Expedition to Torres Straits_, vol. v, p. 206.)

[78] Darwin, _Descent of Man_, p. 164.

[79] While in the majority of women the menstrual cycle is regular for the
individual, and corresponds to the lunar month of 28 days, it must be
added that in a considerable minority it is rather longer, or, more
usually, shorter than this, and in many individuals is not constant.
Osterloh found a regular type of menstruation in 68 per cent, healthy
women, four weeks being the most usual length of the cycle; in 21 per
cent, the cycle was always irregular. See Naecke, "Die Menstruation und ihr
Einfluss bei chronischen Psychosen," _Archiv fuer Psychiatrie_, 1896, Bd,
28, Heft 1.

[80] Among the Duala and allied negro peoples of Bantu stock dances of
markedly erotic character take place at full moon. Gason describes the
dances and sexual festivals of the South Australian blacks, generally
followed by promiscuous intercourse, as taking place at full moon.
(_Journal of the Anthropological Institute_, November, 1894, p. 174.) In
all parts of the world, indeed, including Christendom, festivals are
frequently regulated by the phases of the moon.

[81] It has often been held that the course of insanity is influenced by
the moon. Of comparatively recent years, this thesis has been maintained
by Koster (_Ueber die Gesetze des periodischen Irreseins und verwandter
Nervenzustaende_, Bonn, 1882), who argues in detail that periodic insanity
tends to fall into periods of seven days or multiples of seven.

[82] Ed. Hahn, _Demeter und Baubo_, p. 23.

[83] E. Seler, _Zeitschrift fuer Ethnologie_, 1907, Heft I, p. 39. And as
regards the primitive importance of the moon, see also Frazer, _Adonis,
Attis, Osiris_, Ch. VIII.

[84] Jastrow, _Religion of Babylonia_, 1898, pp. 68, 75-79, 461.

[85] Even in England, Barnes has known women of feeble sexual constitution
who menstruated only in summer (R. Barnes, _Diseases of Women_, 1878, p.
192).

[86] A.B. Holder, "Gynecic Note