Section of Ovary.
1. Graafian follicle in the earliest stage.
2, 3, 4. Follicles in more advanced stages.
5, 7. Almost mature follicle.
6. Follicle from which the ovum has escaped.
8. Corpus luteum.
Corpora Lutea. After the Graafian follicle has burst and the ovum has been pushed out, the cavity that is left does not remain empty and functionless; there is a further process going on there; there is a growth of cells, of a yellowish color, and the follicle becomes filled with a yellowish body, which on account of its color is called the corpus luteum (plural—corpora lutea; luteum in Latin—yellow, corpus—body). This corpus luteum grows in size until it sometimes occupies as much as one-third of the ovary. But there is considerable difference between the corpora lutea of non-pregnant and pregnant women. Up to the end of about a month the corpora lutea are the same, but after that the corpus luteum of the non-pregnant woman begins to get smaller, to shrink, so that at the end of two or three months it is reduced to a small scar and later cannot be noticed at all. The corpus luteum of the pregnant woman keeps on increasing until the end of the second month, remains about the same size until the end of the sixth month, and only then begins gradually to diminish. The corpus luteum of the non-pregnant woman, that is, the one following menstruation, is called false corpus luteum; the corpus luteum following pregnancy is called a true corpus luteum. The corpus luteum acts like a gland and elaborates a secretion which has an influence on the circulation in the uterus and on menstruation. It probably possesses other properties, with which we are not yet quite familiar. The corpora lutea of various animals are now prepared in powder or tablet form and used in medicine in the treatment of certain diseases of women.
SUBCHAPTER B
FUNCTION OF THE OTHER GENITAL ORGANS
Function of the Fallopian Tubes. The function of the Fallopian tubes or oviducts as they are sometimes called is to catch the ovum as it bursts through the ovary and to conduct it from the ovary into the uterus. It is while the ovum is in the narrow lumen of the tube that the spermatozoön which has travelled up from the uterus usually finds it, and it is in the tube, near its entrance to the womb, that impregnation usually takes place. After the ovum is impregnated or fecundated, it slowly moves down to the uterus, where it attaches itself and remains and grows for nine months, until it is ready to come out and start an independent life.
The uterus or womb is the house of the embryo almost from the moment of conception to the moment of birth. Within the thick warm sheltered walls of the uterus the child grows, develops, eats and breathes, until all its organs and functions have reached such a stage of perfection that it can live by itself and for itself. And this may be said to be the sole function of the uterus, or at least its sole useful function. For the other function of the uterus, menstruation, cannot be said to be a necessary or a useful function. It is a normal function because it occurs regularly in every healthy woman during her child-bearing period, but not every normal function is a necessary or useful function. Not everything that is is right or useful.
Function of the Vagina. The vagina is the canal in which sexual intercourse takes place. It receives the male organ (penis) during the sexual act, and serves as a temporary repository for the male semen. After the spermatozoa have reached the uterus, the vagina has no further function to perform.
Functions of the Vulva, Clitoris, and Mons Veneris. The vulva and the clitoris have no special functions to perform; but in them, in the clitoris particularly, but also in the labia minora, resides the feeling of voluptuousness, the pleasurable sensation experienced during the sexual act. Another seat of voluptuousness in the woman is located in the cervix of the uterus.
The mons Veneris has no special physiological function to perform, but it as well as the vulva serve as strong points of attraction for the male sex. While the entire female body is attractive to the male, and vice versa, there are certain zones which are especially attractive or exciting. Such zones or areas are called erogenous zones—the word erogenous means love-generating. The vulva and the mons Veneris are the strongest erogenous zones; other erogenous zones are the lips, the breasts, etc.
Function of the Breasts. The function of the breasts is to nurse or suckle the young on the mother's milk until they are able to live on other food. The other name for breasts is mammary gland (in Latin, mamma—breast), and all animals who suckle their young are called mammals or mammalia. Besides its milk secreting function, the breasts constitute a strong erogenous zone; they are a point of strong attraction for the male sex, many men being more attracted by well-developed breasts than by a pretty face. There is a good biological reason for this. Well developed breasts indicate that the other sexual organs are well developed and that the woman will make a satisfactory wife and satisfactory mother. Considering then the importance of the breasts in attracting a husband and their function in nursing the young, also their erogenous properties, it is perfectly proper to class them among the reproductive organs.
SUBCHAPTER C
THE ORGASM
The culmination of the act of sexual intercourse is called the orgasm. It is the moment at which the pleasurable sensation is at its highest point, the body experiences a thrill, there is a spasmodic contraction in the genital organs, and there is a secretion of fluid from the genital glands and mucous membranes. This fluid in women is not a vital fluid like the semen in man; it is merely mucus, and in some women it is very slight in amount or altogether absent. Adult women who live without sexual relations occasionally have sexual or erotic dreams; that is, they dream that they are in the company of men, playing or having relations with them. Such dreams are usually accompanied by an orgasm or an orgastic feeling, and by a discharge of mucus, the same as in sexual intercourse. Such a discharge of mucus during sleep is called an emission or pollution.
In the male sex pollutions play an important rôle (see the author's "Sex Knowledge for men"), because the semen is a vital fluid, and if it is lost too frequently the system is put under a heavy drain. In boys and men the pollutions or night losses may occur several times a week or even every night, or several times a night. When they occur with such frequency the man may become a wreck. Not so with women. First, pollutions or night dreams in women are much more rare than they are in men; and second, as just mentioned, the fluid secreted by woman during intercourse or during an erotic dream is not of a vital character, as the semen is in man; it is mucus, and the secretion of a mucous fluid, even if somewhat excessive, does not constitute a drain on the system. For this reason women can stand frequently repeated sex relations and emissions or pollutions much better than men can.
SUBCHAPTER D
THE SECONDARY SEX CHARACTERS
The sex organs constitute the primary sex characters. It is they that distinguish primarily one sex from another. But there are numerous other sex characters or sex differences which while not so important serve to differentiate the sexes, at the same time forming points of attraction between one sex and another. For instance, the beard and mustache are a distinct