precursor of all the cut-up worms, of the frogs, birds, and guinea-pigs that have been beheaded, or have had their brain removed, or their nerves cut, and have furnished further examples of this divisibility of “souls.” If the independence of the spiritual is thus shown to be a vain assumption, the alleged difference between the animal and the human Psyche is much more so. Not from the days of Darwinism alone, but from the very beginning, naturalism has opposed this claim to distinctiveness. But it is due to Darwinism that the fundamental similarity of the psychical in man and animals has come to be regarded as almost self-evident. The mental organisation of man, as well as his corporeal organisation, is traced back through gradual stages to animal antecedents, and in thus tracing it there are two favourite methods of procedure, which are, however, apt to be mutually destructive. On the one hand, some naturalists regard the animal anthropomorphically, insist on its likeness to man, discovering and extolling, not without emotion, all the higher and nobler possessions of the human mind, intellectual capacities, reason, reflection, synthesis, fancy, the power of forming ideas and judgments, of drawing conclusions and learning from experience, besides will in the true sense, ethical, social and political capacities, æsthetic perceptions, and even fits of religion in elephants, apes, dogs, down even to ants and bees, and these naturalists reject old-fashioned explanations in terms of instinct, and find the highest already contained in the lowest. Those of another school are inclined to regard man theriomorphically, to insist on his likeness to animals, explaining reason in terms of perception and sensation, deriving will from impulse and desire, and ethical and æsthetic valuations from physiological antecedents and purely animal psychological processes, thus, in short, seeking to find the lowest in the highest. (We have already met with an analogous instance of a similarly fallacious double-play on parallel lines.) So it comes about that both the origin and the development of the psychical and spiritual seem to be satisfactorily cleared up and explained, and at the same time a new proof is adduced for its dependence upon the physical. For what is true of all other parts of the organisation, of the building up and perfecting of every member and every system of organs, the bony skeleton, the circulatory system, the alimentary canal, that they can be referred back to very simple beginnings, and that their evolution may be traced through all its stages—is equally true of the nervous system in general and of the brain in particular. It increases more and more in volume and in intricacy of structure, it expands the cranial cavity and diversifies its convolutions. And the more it grows, and the more complex it becomes, the more do the mental capacities increase in perfection, so that here again it seems once