Among the nations of the Old World certain plants have been under domestication for so long a time, and have varied so greatly, that the wild species from which they came are no longer known. This is true of nearly all our common fruits and vegetables and many of our flowers that were derived from the Old World. At the time of the Spanish conquest the aborigines of America were cultivating tobacco, potatoes, beans, tomatoes, squashes, maize, cotton, etc., and in the case of most of these plants the wild species from which they were derived has not been ascertained. The argument that points to a great antiquity in the case of wheat and the peach applies equally well to tobacco and maize, and indicates that horticulture began in America in remote antiquity. At the time of Columbus, the ox, sheep, goat, pigeons, fowls, cat, etc., long domesticated in the Old, were absent in the New World, and the llama, turkey, etc., indigenous in America, were unknown in Europe. These striking differences, among which there is not even a single exception, amount to positive evidence that contact between the peoples of the Old and the New World did not occur after the inhabitants of the former emerged from savagery, or, what is the same thing, never existed in the sense that trade relations were entered into. This same line of argument seemingly casts grave doubts on the deductions already referred to concerning the importation into America from Polynesia of the practise of tattooing, the wearing of masks, the use of labrets, etc.; and indicates also that but slight changes were produced in the American aborigines owing to the wrecking of Asiatic junks on the northwest coast. Another factor bearing on the antiquity of the indigenous Americans is the stage of development reached in spite of their long and nearly complete isolation. Stimuli from without, and particularly contact with more advanced peoples, having been lacking or of small importance, incentive to bodily and mental activity arose mainly from the desire for food, clothing, and shelter, and from intertribal rivalry, jealousy, and war. This process of indigenous development was certainly slow. With man, as with the lower animals, the rate of advance and of specialization increases as higher and higher grades of development are reached. For the American aborigines to have attained the higher stages of barbarism at the time of the arrival of civilized Europeans, solely by self-growth and self-education, is perhaps even a stronger argument for their antiquity than their differentiation in culture, languages, etc. These several lines of evidence point to the coming of man to America as an event of the far distant past--a time so remote, in fact, that it pertains to geology rather than to ethnology.