All the important results of comparative morphology and physiology, which the modern supporters of the doctrine of descent so confidently utilise as arguments in its favour, would have been welcomed by those who held the original and general evolution idea, as a corroboration of their own standpoint. And as a matter of fact they all afford conclusive proofs of _evolution_; but not one of them, including even the fundamental biogenetic law and the inoculated chimpanzee, is decisive in regard to _descent_. This contention is sufficiently important to claim our attention for a little. Let us take the last example. Transfusion of blood between two species is possible, not necessarily because they are descended from one another or from a common root, but solely because of their systematic (ideal) relationship, that is to say because they are sufficiently near to one another and like one another in their physiological qualities and functions. If, assuming descent, this homology were disturbed, and the systematic relationship done away with, for instance through saltatory evolution, the mere fact of descent would not bring the two species any nearer one another. Thus the case proves only systematic relationship, and only evolution. But as to the meaning of this systematic relationship, whether it can be “explained” by descent, whether it has existed from all eternity, or how it has arisen, the experiment does not inform us. The same idea may be illustrated in regard to Weismann’s “predicting.” This, too, is a proof of evolution, but not of descent. Exactly as Weismann predicted the striping of the hawk-moth caterpillars and the human _os centrale_, Goethe predicted the formation of the skull from modified vertebræ, and the premaxillary bone in man. In precisely the same way he “derived” the cavities in the human skull from those of the animal skull. This was quite in keeping with the manner and style of his Goddess Nature and her creative transformations, raising the type of her creations from stage to stage, developing and expanding each new type from an earlier one, yet keeping the later analogous to and recapitulative of the earlier, recording the earlier by means of vestigial and gradually dwindling parts. But what has all this to do with descent? Even the “biogenetic law” itself, especially if it were correct, would fit admirably into the frame of the pure evolution idea. For it is quite consistent with that idea to say that the higher type in the course of its development, especially in its embryonic stages, passes through stages representative of the forms of life which are below it and precede it in the (ideal) genealogical tree. Indeed, the older doctrine of evolution took account of this long ago.