CRIMINALS: The inmates of prisons, penitentiaries, reformatories, and similar places of detention numbered 111,609 in 1910; this does not include 25,000 juvenile delinquents. The jail population is nearly all transient; one must be very cautious in inferring that conviction for an offense against the law indicates lack of eugenic value; but it is worth noting that the number of offenders who are feeble-minded is probably not less than one-fourth or one-third. If the number of inebriates could be added, it would greatly increase the total; and inebriacy or chronic alcoholism is generally recognized now as indicating in a majority of cases either feeble-mindedness or some other defect of the nervous system. The number of criminals who are in some way neurotically tainted is placed by some psychologists at 50% or more of the total prison population. Add to these a number of epileptics, tramps, prostitutes, beggars, and others whom the census enumerator finds it difficult to catch, and the total number of possible undesirable parents becomes very large. It is in fact much larger than appears in these figures, because of the fact that many people carry defects that are latent and only appear in the offspring of a marriage representing two tainted strains. Thus the feeble-minded child usually if not always has feeble-mindedness in both his father's and mother's ancestry, and for every one of the patent feeble-minded above enumerated, there may be several dozen latent ones, who are themselves probably normal in every way and yet carry the dangerously tainted germ-plasm. The estimate has frequently been made that the United States would be much better off eugenically if it were deprived of the future racial contributions of at least 10% of its citizens. While literally true this estimate is too high for the group which could be considered for attempts to directly control in a practical eugenics program.