Various estimates of the size of the aboriginal Indian population of North America exist, but there is agreement on a figure of less than a million and perhaps less than 750,000. By 1850, disease, dissipation, starvation, mas sacre, and maladaptation had reduced the population to a quarter million. This figure remained until 1900, but has since risen to about 400,000. Now the In dian net natural increase is higher than that for the total population of the coun try. The Indian population has a much higher proportion of persons under 25 years of age, which with other factors suggests that by 1975 there will be over 700,000 Indians in our country.—Ed.