Plain Facts for Old and Young

by John Harvey Kellogg

[ANATOMY OF THE REPRODUCTIVE ORGANS.]

Having now considered the functions and somewhat of the structures of the principal organs of reproduction, we may obtain a more definite idea of the relation of the several organs of each class by a connected review of the anatomy of the parts.

[Male Organs.]—As previously stated, the external organs of generation in the male are the penis and the testicles, the latter being contained in a pouch called the scrotum. The penis is the organ of urination as well as copulation. Its structure is cellular, and it contains a vast number of minute coils of blood-vessels which become turgid with blood under the influence of sexual excitement, producing distention and erection of the organ. A canal passes through its entire length, called the urethra, which conveys both the urine and the seminal fluid. The organ is protected by a loose covering of integument which folds over the end. This fold is called the foreskin or prepuce.

The fluid formed by each testicle is conveyed by the vas deferens, a curved tube about two feet in length, to the base of the bladder. Here the vas deferens joins with another duct which communicates with an elongated pouch, the vesicula seminalis, which lies close upon the under side of the bladder. The single tube thus formed, the ejaculatory duct, conveys the seminal fluid to the urethra, from which it is discharged.

As the production of seminal fluid is more or less constant in man and some animals, while its discharge is intermittent, the vesiculæ seminales serve as reservoirs for the fluid, preserving it until required, or allowing it to undergo absorption. Some claim that the zoösperms are matured in these organs. They always contain seminal fluid after the age of puberty. During coition, their contents are forcibly expelled by a spasmodic contraction of the muscles which surround them and the ducts leading from them.

[The Prostate Gland.]—Surrounding the ejaculatory ducts and their openings into the urethra at the base of the bladder is the prostate gland, which produces a peculiar secretion which forms a considerable portion of the seminal fluid, being mingled with the secretion of the testes during its ejaculation. This gland sometimes becomes the seat of somewhat serious disease. In old age it usually becomes somewhat indurated, and often to such an extent as to seriously affect the health and comfort of the individual by interference with urination and by occasioning pain.

Anterior to this organ, in the urethra, is a curious little pouch, the utriculus, which corresponds to the vagina and uterus in the female. Just in front of the prostate gland are two small bodies known as Cowper's glands. They secrete a fluid which combines with the seminal secretion.

[Female Organs.]—The ovaries, uterus, or womb, Fallopian tubes, and vagina have already been described in part. The external organs of the female are included in the term vulva or pudenda. The most superficial parts are the labia, two thick folds of integument. Just within these are two thinner folds, the labia minora or nymphæ. These, together with the clitoris, situated just above, are extremely sensitive organs, being the chief seat of sexual sense in the female. At the lower part is the opening to the vagina, which in the virgin is usually partially guarded by a thin membrane, the hymen. This is not always a reliable test of virginity, however, as commonly regarded, since it may be destroyed by disease or accident, and may exist even after the occurrence of pregnancy.

The vagina extends from the vulva to the lower end of the uterus, which it incloses, passing between the bladder and the rectum. The lower extremity of the uterus presents a small opening which leads into its interior. Upon either side, at its upper and larger end, is a minute opening, the mouth of the Fallopian tube. The latter organs extend from the uterus outward nearly to the ovaries, toward which they present a number of small filaments, one of which is in contact with each ovary. These filaments, together with the interior of the tubes, are covered with a peculiar kind of cells, upon which are minute cilia, or hairs, in constant motion. Very curiously, they all move in the same direction, toward the cavity of the uterus. When an ovum escapes from the ovary in connection with menstruation, it is by these delicate hairs propelled along a filament of tissue to the Fallopian tube, and thence by the same means is conveyed to the uterus. It may come in contact with the zoösperms at any point between the ovary and the lower orifice of the uterus, and thus undergo fecundation.

[Puberty.]—For a certain period after birth, the sexual organs remain in a partially developed condition. This period varies in duration with different animals; in some cases being very brief, in others, comprising several years. Upon the attainment of a certain age, the individual becomes sexually perfect, and is then capable of the generative act. This period is called puberty. In man, puberty commonly occurs between the ages of ten and fifteen years, varying considerably in different climates. In this country, and in other countries of about the same latitude, puberty usually occurs at the age of fourteen or fourteen and one-half years in females, and a few months later in males. In cooler climates, as in Norway and Siberia, the change is delayed to the age of eighteen or nineteen years. In tropical climates it is hastened, occurring as early as nine or ten years. In warm climates it is no uncommon thing for a girl to be a mother at twelve; and it is stated that one of the wives of Mahomet was a mother at ten.