Thus Nature works with the eternal justice of eternal reciprocity between the sexes; making them all the while more complexly diverse, but nevertheless more closely interdependent. So that one sex can neither progress nor can it regress by itself; but draws the other onward with it, or drags it back. Thus, the bread of human heritage consigned to the stream of posterity by one sex, for equipment and furtherance of the other, returns to the hand of the sex that consigned it.
If this be so—and I hope to prove it so—the woman who develops the potential male in her defrauds of its lawful racial and personal entail not only the opposite sex, in the person of her son, but she defrauds of its dower her own sex too, in the person of her grand-daughter.
Of the interesting and important biological processes underlying the mystery of the Dual-Sex constitution and its manifold phenomena, I am about to present a wholly new and—I venture to believe—a wholly true and convincing elucidation.
Natura simplex est, said Newton, et sibi semper consonans. (Nature is simple and always agrees with herself.) Bewilderingly multiple in her phenomena, she is superbly simple in her principles. By the operation of her one great Law of Gravitation, she sustains the mighty Solar systems—and brings the apple to the ground. By the extension, counterpoise and co-operation of one Primal Cosmic Energy—with its dual impulses, Centripetal and Centrifugal—she has generated all the diverse marvels of a Universe. And in view of her simplicity of Principle, it is conceivable that the Duality of Sex may be an extension into Life of that same principle of Duality which characterises the vaster Cosmic phenomena.
If this be true, Man and Woman are the complex resultant of infinitely many and varied evolutionary differentiations and associations of the two modes of Primal Energy. If so, the principle of Sex must have existed before Matter; must have been inherent in Creation before Creation began to evolve. And if so, Evolution would seem to have had for its purpose the ever further and fuller manifestation of these dual and contrary inherences in terms of Life and Sex. While, to judge by effects, it has had for its means such ever more intimate and intricate co-operations of these as have resulted in the progressively diverse and complex developments found to-day in Human Life and Human Sex-Characteristics.
CHAPTER III
THE MYSTERY OF SEX AND SEX-TRANSMISSION
"The idea that the female is naturally and really the superior sex seems incredible, and only the most liberal and emancipated minds, possessed of a large store of biological information, are capable of realising it."—Professor Lester Ward.
I
Those happy persons who do not perplex themselves concerning the intrinsic causes behind all physical phenomena see it as only "natural" that two parents of opposite sex should produce offspring of both sexes.
And yet it is not only a great mystery, but, on the face of it, it is an anomaly that a child who may possess an admixture of all the physical and mental characteristics of its two parents, bears, nevertheless, the sex and the sex-characteristics of one only. Sex, male or female, breeds true in nearly every case; the rare exceptions merely emphasising the rule. The mystery deepens when we realise that every individual is a product of countless such admixtures of the qualities, throughout countless generations, of countless forefathers and foremothers. And although such a man or woman may hark back to any one, or more, of the traits of his or her innumerable forbears, he or she, nevertheless, "breeds true" in the factors of sex and sex-characteristics.
Long and closely biologists have pondered these many and involved problems. How is it, they inquire, that an embryo bred of two parents of opposite sex develops the sex of one only of these? How is it that the mother, who belongs to one sex only, produces—and produces in about equal number—offspring of both? The phenomenon is expressed, biologically, in the term, "sex-limited factor"—an incalculable something in the embryo which limits its sex to the sex of one only of its parents. But the "something," and the method of this sex-limitation have remained enigmas.
Sex is regarded by the new Mendelian school of biologists as that which is known as a "Mendelian factor." And to follow the argument to its conclusions, a few simple words about the Mendelian theory of Heredity are essential to those unacquainted therewith.
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About forty years ago, a German monk, Mendel by name, was struck by the facts that in his bed of edible peas certain plants grew tall, while others remained dwarf; that the blossoms of certain plants were white always, while those of others were always coloured. He made a number of experiments in crossing the plants, with a view to discovering the law of inheritance by way of its operation in hybrid varieties. Briefly, the results of his experiments—which have since been repeated and confirmed by many later observers—were as follows:
There are plants that are tall and can transmit only Tallness to offspring. There are plants that are dwarf and can transmit only Dwarfness to offspring. So too, there are plants of white blossom or of coloured blossom that can transmit, respectively, only White or Coloured blossoming to offspring.
When a Tall is crossed with a Dwarf plant, however, or a Coloured with a White plant, strange to say, the hybrid offspring of this cross shows one only of these opposite traits, to the exclusion of the other. No intermediate, or mixed, forms are produced.
Thus, a Tall crossed with a Dwarf produces only Talls. Plants of Coloured flower crossed with those of White flower give only Coloured flowering varieties. A yellow and a green-seeded cross produce only yellow-seeded plants.
In the cross between plants of opposite traits, one set of traits appears thus, exclusively, in the hybrid offspring. These traits—because they dominate growth and development—Mendel styled "Dominant." While those traits which are dominated by the other and opposite traits and do not appear in offspring, he styled "Recessive."
On further breeding, a new and stranger thing happens, however. Because when such hybrids—plants bred of parents that had borne, respectively, "Dominant" and "Recessive" characteristics, but with the parental Dominant traits so overpowering the Recessive traits of the other parent that these latter are submerged and concealed—When these hybrids are crossed with other hybrids like themselves, both the Dominant and the Recessive traits of the original parents reappear in offspring. The tall hybrids resulting from the cross between Tall and Dwarf plants, when crossed with other tall hybrids of similar origin, produce both Tall and Dwarf plants. So with Colour, and with the other so-called "Contrasted Traits."
It becomes evident, therefore, that although the Dominant traits of Tallness and Colour overpower in the growth and development of the second generation of plants, the Recessive traits of Dwarfness and Whiteness, these latter traits are submerged only, and are neither impaired in their values, nor destroyed. In the third generation, under different conditions of mating, the original Recessive, and submerged, traits re-appear, and reveal themselves in offspring-plants as the Dwarfness or the Whiteness that had characterised their grandparents.
Mendel assumed that such hybrid plants—offspring of a Dominant and of a Recessive parent—produce two varieties of sex-cells, or gametes, and that one order of cells contain the Dominant traits of the Dominant parent, while the other order contain the Recessive traits of the Recessive parent.
But any individual sex-cell, or gamete, cannot (according to his view) bear both Dominant and Recessive traits. The Dominant traits and the Recessive traits of the respective parents he regarded as being segregated, absolutely, in one or in the other set of sex-cells produced by hybrid varieties. And of these, the cells bearing Dominant traits are able to transmit Dominant traits only to offspring; while the cells bearing Recessive traits transmit Recessive traits only to