It is easy to understand that such investigations are very laborious. In order to throw light on the meaning of comparatively insignificant data, it may be necessary to organize most comprehensive researches. Unceasing care and indefatigability in such isolated observations, and in the interpretation of their meaning, is one of Lombroso’s highest claims to honour. For this reason, his books and the thirty volumes of his archives will remain for many decades to come a rich mine of discovery for anthropology, as soon as this science returns from the study of Mongols and Australians to the examination of contemporary Europeans. As a result of these investigations, the fact has been established that, above all in the skulls and the brains of criminals, but also in other parts of the skeleton, in the muscles, and in the viscera, we find anatomical peculiarities, which in some cases resemble the characters of the few authentic remnants of the earliest prehistoric human beings, in other cases correspond to the characters of still extant lower races of mankind, and in yet others, correspond to the characters of some or all of the varieties of monkey. From these facts Lombroso draws a somewhat rash conclusion—namely, that there are born criminals, representing the type of mankind which existed before the origin of law, the family, and property, and that the representatives of long past conditions thus thrust upon our own time are incapable of respecting the security of life and property and other legal rights; but, bold as this conclusion seems, it has, none the less, all the qualities of a scientific conjecture, inasmuch as it harmonizes with all the known facts, and enables us to deal in an orderly and critical manner with the material upon which it bears. I leave the question open whether we are to regard this idea as a theory or merely as a hypothesis; but it is necessary to point out, in opposition to the obstinate assertions of Lombroso’s opponents, that the Italian school of anthropology has never maintained the proposition that all persons who come before European courts of justice upon criminal charges, or all who are confined in the criminal prisons of Europe, are the unchanged descendants of the Neanderthal men, who hunted the cave-bear with stone arrows. Put as concisely as possible, the doctrine of the Italian school runs as follows: Born criminals exist, presenting typical characters, both bodily and mental, and they owe their peculiar organization to the fact that their development has been affected by an atavistic reversion. It is impossible here to give particulars showing the manner in which, in the five successive editions of “L’ uomo delinquente,” this conception becomes gradually more clearly defined.