If Dominance is Maleness, and Recessiveness is Femaleness, and if Dominance energises structural development while Recessiveness engenders reproduction, a Dominant self-fertilising plant is a female plant, with a male plant of superior Dominance differentiated in it. While a Recessive self-fertilising plant is a female plant of superior Recessiveness, with a male plant of inferior Dominance differentiated in it. In crossing stock of superior Dominance with stock of superior Recessiveness, the Dominant prevails over the Recessive in the general structural traits of the resulting "hybrid," but not in its reproductive inherence. The new hybrids being male in inherence, nothing is added to the female reproductive, or Vital, potential in them. The root-stock transmits to its sex-cells therefore just as its grandmother did--Recessives of her type, and Dominants of the type of the Dominant male engrafted on her, of the male grandfather of this third generation, that is. Hence reversion. VI _Sterility of offspring of alien species proves evolution of Species and of Individual are independent phenomena_ The fact that dog and wolf, when mated, breed fertile species, proves them sprung from the same root-stock. While the hybrid offspring of different species are sterile. Showing such an intrinsic incompatability of the alien complements in the zygote as, while operating as no bar to their immediate union and their development into a complete hybrid individual, nevertheless bars the incorporation of the alien breed in the Vital potential of stock. Such sterility in the offspring of creatures of different species is weighty evidence that the Evolution of Type, or Species, and the Evolution of the Individual are wholly independent phenomena; occurring upon wholly different planes, and involving wholly different principles and sets of processes. In the mating of alien species, the two sex-cells, although of dissimilar species-inherence, unite nevertheless and develop in the maternal environment into a living entity of mongrel order. But the Germ-plasm contained in the gamete of one species will not germinate in the alien environment of an organism of alien species. No potential, either Vital or of Differentiation, is engendered, therefore, for production of offspring. Hence sterility results. The potential of a living individual is seen thus to belong to a wholly different plane of phenomena from the potential of Stock. Conditions which do not annul the powers of life and of function in the one, quench life and function in the other with the seal of sterility. VII _Possible explanation of "Sports"_