family—that reproduction develops nature's basic principle of perpetuation in the highest and worthiest manner, in obedience to laws humane and divine.

CHAPTER II

THE TRANSITION FROM CELL TO HUMAN BEING

In the functional processes alluded to in the preceding chapter, the male germ-cell and the female germ-cell unite in a practically equal division of substance. We say “practically” because the maternal and the paternal influences are not equally divided in the offspring. One or the other usually predominates. But, as a general rule, it may be said that in the development of the embryonal life the process of cell division proceeds in such a way that every germ of the child's future organism represents approximately one-half maternal and one-half paternal substance and energy.

In this process lies the true secret of heredity. The inherited energies retain their full measure of power, and all their original quality in the growing and dividing chromosomes (the chromosome is one of the segments into which the chromoplasmic filaments of a cell-nucleus break up just before indirect division). On the other hand, the egg-substance of the female germ-cell, which is assimilated by the chromosomes, and which is turned into their substance by the process of organic chemistry, loses its specific plastic vital energy completely. It is in the same way that food eaten by the adult has absolutely no effect on his qualitative organic structure. We may eat ever so many beef-steaks without acquiring any of the characteristics of an ox. And the germ-cell may devour any amount of egg-protoplasma without losing its original paternal energy. As a rule a child inherits as many qualities from its mother as from its father.

DETERMINATION OF SEX

Sex is determined after conception has taken place. At an early stage of the embryo certain cells are set apart. These, later, form the sex glands. Modern research claims to have discovered the secret of absolutely determining sex in the human embryo, but even if these claims are valid they have not as yet met with any general application.

EARLY DEVELOPMENT

Some twelve days after conception, the female ovule or egg, which has been impregnated by the male spermatazoön, escapes from the ovary where it was impregnated, and entering a tube (Fallopian) gradually descends by means of it into the cavity of the womb or uterus. Here the little germ begins to mature in order to develop into an exact counterpart of its parents. In the human being the womb has only a single cavity, and usually develops but a single embryo.

TWINS

Sometimes two ovules are matured at the same time. If fecundated, two embryos instead of one will develop, producing twins. Triplets and quadruplets, the results of the maturing of three or four ovules at the same time, occur more rarely. As many as five children have been born alive at a single birth, but have seldom lived for more than a few minutes.

GESTATION

The development of the ovule in the womb is known as gestation or pregnancy. The process is one of continued cell division and growth, and while it goes on the ovule sticks to the inner wall of the womb. There it is soon enveloped by a mucous membrane, which grows around it and incloses it.

THE EMBRYO

The Primitive Trace, a delicate straight line appearing on the surface of the growing layer of cells is the base of the embryonic spinal column. Around this the whole embryo develops in an intricate process of cell division and duplication. One end of the Primitive Trace becomes the head, the other the tail, for every human being has a tail at this stage of his existence. The neck is marked by a slight depression; the body by a swollen center. Soon little buds or “pads” appear in the proper positions. These represent arms and legs, whose ends, finally, split up into fingers and toes. The embryonic human being has been steadily increasing in size, meanwhile. By the fifth week the heart and lungs are present in a rudimentary form, and ears and face are distinctly outlined. During the seventh week the kidneys are formed, and a little later the genital organs. At two months, though sex is not determined as yet, eyes and nose are visible, the mouth is gaping, and the skin can be distinguished. At ten weeks the sexual organs form more definitely, and in the third month sex can be definitely determined.

THE FOETUS

At the end of its fourth month the embryo—now four or five inches long and weighing about an ounce—is promoted. It receives the name of foetus. Hairs appear on the scalp, the eyes are provided with lids, the tongue appears far back in the mouth. The movements of the foetus are plainly felt by the mother. If born at this time it lives but a few minutes. It continues to gain rapidly in weight. By the sixth month the nails are solid, the liver large and red, and there is fluid in the gall bladder. The seventh month finds the foetus from twelve and a half to fourteen inches long, and weighing about fifty-five ounces. It is now well proportioned, the bones of the cranium, formerly flat, are arched. All its parts are well defined, and it can live if born. By the end of the eighth month the foetus has thickened out. Its skin is red and covered by a delicate down; the lower jaw has grown to the same length as the upper one. The convolutions of the brain structure also appear during this month.

PLACENTA AND UMBILICAL CORD

During gestation the unborn infant has been supplied with air and nourishment by the mother. An organ called the Placenta, a spongy growth of blood vessels, develops on the inner point of the womb. To this organ the growing foetus is moored by a species of cable, the Umbilical Cord. This cord, also made up mainly of blood vessels, carries the blood of the foetus to and from the Placenta, absorbing it through the thin walls which separate it from the mother's blood. Only through her blood can the mother influence the child, since the Umbilical Cord contains no nerves. The Umbilical Cord, attached to the body of the child at the navel, is cut at birth, and with the Placenta is expelled from the womb soon after the child has been born. Together with the Placenta it forms a shapeless mass, familiarly known as the “afterbirth,” and when it is retained instead of being expelled is apt to cause serious trouble.

CHILDBIRTH OR PARTURITION

At nine month's time the foetus is violently thrust from that laboratory of nature in which it has formed. It is born, and comes into the world as a child. Considering the ordinary size of the generative passages, the expelling of the foetus from the womb would seem impossible. But Nature, during those months in which she enlarged the womb to hold its gradually increasing contents, has also increased the generative passages in size. She has made them soft and distensible, so that an apparent physical impossibility could take place, though it is often accompanied by intense suffering. Modern medical science has made childbirth easier, but the act of childbirth is usually accompanied by more or less suffering. Excessive pain, however, is often the result of causes which proper treatment can remove before and at the time of confinement.

TWILIGHT SLEEP

The so-called “Twilight Sleep,” a modern development, by which the pangs of childbirth are obviated by the administration of drugs or by hypnotic suggestion, has its opponents and defenders. The advantage of a painless childbirth, upon which the mother can look