44 ADAMITES AND PREADAMITES.
II. Geological evidence. The forms of organization which have populated the world in its remote preparatory stages have been as diverse as the successive stages. Types of organization suited to a rude condition of the world demanded improvement when the conditions had improved. Fossil remains indicate that such improvements took place. It was not the displacement of the old type by the new, but a modification of the old type. So the general types of animals with which the world began to be populated in its infancy continue in existence. If we take a particular existing type, as the proboscidian, we learn from the testimony of fossils, that it is a modification of a type which existed in the last geological age before the present. That was a modification of an older one, and that of a still older, and so on. If we take the existing type of ox, or hog, or horse, we discover in each case a series of older modifications of the type reaching back through Tertiary time. In the case of the horse the series of known forms is remarkably full. (See Reconciliation of Science and Religion, pp. 166-17o.) Now these series of successions receding into the past constantly converge. That is, the ancient proboscidian type differed less from the hog or horse type than the modern one does. All the ancient types approximated each other. In some cases two or three types are found actually merged together. The judgment cannot resist the conviction that some distance farther back they all converge. Thus the modern types of mammals have diverged from a common five-toed, plantigrade,primitive form. But all this is no proof of genetic relationship in the terms of each series. All this might be if each term were a new beginning—an independent creation. This evidence is onlya link in the proof.
III. Variational evidence. A species is now known not to be " a primordial organic form," as defined by Morton, but only a phase in a series of changes. That species vary to a wide extent has lately been shown by the study of many thousands of American birds. One-fourth of all our recognized species are only geographical varieties. The variations had become so wide that all naturalists recognized these varieties as good species. . Some-thing similar is true of our mammals. In short, it is now generally admitted that a large fraction of all hitherto recognized species are only varieties of certain forms which we must continue to