: after the corpus luteum, the placenta: after the
placenta, the mammary glands: after that the cycle begins again until
the ovaries are exhausted and the chain is broken. Besides, all the
other glands of internal secretion beat in rhythm, fluctuate in their
activities, may divide prematurely the tides or dam them completely.

Innumerable varieties and combinations of interglandular action supply
us with the limitless types of adolescent girls. Some endocrine
cooperatives that make one girl stable and settled, will make others
unstable and unsettled. Alicia may be hyperthyroid, and so excitable,
nervous, restless, and subject to palpitation of heart and
sleeplessness. Bettina may have too much post-pituitary, and so will
menstruate early, tend to be short, blush easily, be sentimentally
suggestive and sexually accessible. Christina may be adrenal cortex
centred and so masculinoid: courageous, sporty, mannish in her tastes,
aggressive toward her companions. Dorothea may have a balanced thyroid
and pituitary and so lead the class as good-looking, studious, bright,
serene and mature. Florence, who has rather more thyroid than her
pituitary can balance, will be bright but flighty, gay but moody,
energetic, but not as persevering. And so on and so on.

Environment, habit-formation, training, education serve only to bring
out the internal secretion make-up of the girl, or to suppress
and distort and so spoil her. Adolescence will be peaceful, calm,
semi-conscious, or disturbing, revolutionary and obsessive according
to the reaction of the other endocrines to the rise of the ovaries.
Harmony, and so continued happiness of the mind and body, means
that they have been welcomed into the fold. Disharmony, ailments,
unhappiness, difficulties, mean that they are being treated as
intruders, or are acting as marauders. The after life, sexually the
period of maturity, barring accidents, diseases, and shocks, will bear
the same character. The kind of adolescence provides the clue to the
kind of maturity, for both are effects of the same endocrine factors.

THE SEX GLAND CHAIN

Furthermore, the activities of a normal woman involve a series of sex
glands. Since there function, in addition to the ovaries, the glands
of the uterus, the breasts or mammary glands, and the placental
gland (the secreting cells of the tissue which comes out as the
after-birth). Each of these contributes directly to the reproductive
life of the individual. To