How we may or can picture this as occurring is a question which of course admits only of being answered very hypothetically, and it leads us, moreover, into the region of the fundamental phenomena of life, with the interpretation of which we are not here concerned. For the present we have assumed that life is a chemico-physical phenomenon, and we have postponed the deeper explanation of it to the remote future, that we may confine ourselves in the meantime to the solution of the problem of inheritance on the basis of the forces resident in the vital elements. But we may, nevertheless, make the supposition that a kind of struggle between the different kinds of biophors may take place within the cell, if the homologous determinants of all the ids for the control of the cell have entered into it. In many cases this struggle will be decided by the numerical preponderance of one kind of determinant over the other, but it is certainly conceivable that dynamic differences may also have something to do with it. Let us, however, abstain from trying to penetrate further into the obscurity of these processes, and let us content ourselves with establishing that the preponderance of one parent in some or many parts of the child may be almost if not quite complete, and that this compels us to assume that the hereditary substance of the other parent is in such cases rendered inoperative--for we know it is present--since the ids of both parents all go through the whole ontogeny, and are contained in every somatic cell. Upon this struggle between homologous determinants depends the possibility of the entire suppression or inhibition of the influence of one parent, the whole diversity in the mingling of paternal and maternal character in the body of the offspring. It is in this that we must seek the explanation of the fact that not only whole bodily parts of the child, such as arms, legs, the nature of the skin, the form of the skull, may take after sometimes the father, sometimes the mother wholly or predominantly, but that the small separate subdivisions of a complex organ may sometimes turn out more maternal, sometimes more paternal. Thus intelligence from the mother and will from the father, musical talent from the father and a talent for drawing from the mother, may be inherited by the same child. I do not doubt that genius depends in great part on a happy combination of such mental endowments of the ancestors in one child. Of course something more is necessary, namely, the strengthening of certain of these hereditary endowments, but of this we shall speak later.