the improved condition of things, successively appeared, until, at the latest epoch, man entered upon the scene, the head of animated nature as at present constituted, with powers and capacities well adapted for the full enjoyment of the augmented riches of the earth. And the end is not yet. "The present race, rude and impulsive as it is, is perhaps the best adapted to the present state of things in the world; but the external world goes through slow and gradual changes, which may leave it in time a much serener field of existence. There may then be occasion for a nobler type of humanity, which shall complete the zoölogical circle on this planet, and realize some of the dreams of the purest spirits of the present race."
The question now occurs, How are we to account for the origin of life, both in the vegetable and animal kingdoms? The answer can readily be given, if we follow out resolutely to their remotest consequences the principles that have already been established. The evolution of