At the afternoon session, presided over by Professor Ladame (Geneva), M. Ferri read a paper on the determining conditions of crime--individual, physical, and social--and their relative value. M. Ferri is one of the most accomplished and philosophic advocates of the new criminal anthropology, and his paper, and its subsequent eloquent elucidations, were listened to with great attention. Crime, he said, is at once biological and social. Out of 100 persons living in the same conditions of misery and abandonment, 60 commit no crimes; of the other 40, 5 commit suicide; 5 become insane, 5 are beggars, 25 commit crimes; therefore the social environment is not the exclusive cause of crime. But, again, we must not neglect the social environment, for, to mention one piece of evidence only, the maximum of crimes against property is reached in winter. And, again, the most delicate biological modifications must be considered, for rapes and crimes of violence are most common when the temperature is high, and climate and barometrical pressure play a certain part. If the thermometer had marked ten degrees less, or the barometer a few millimetres more, perhaps such and such a crime would not have been committed. The conclusion is that, on the one hand, we must ameliorate social conditions for the natural prevention of crime, and on the other hand exercise measures of temporary or perpetual elimination of individuals, according as the biological conditions in each case seem more or less curable. M. Alimena attached great importance to education, especially to its hereditary effects. The criminal ought not to be able to say to his judge: “Why have you not made me better?” He agreed with the words of Lacassagne at the former Congress at Rome: “Societies have the criminals that they deserve.” M. Manouvrier considered that Ferri did not attach enough importance to the social factor; no two persons lived in the same social environment. This was also the opinion of M. Drill. M. Tarde expounded his views as to the characteristics of criminals being due to the professional exercise of crime. M. Féré would not believe in any professional type until it had been established by precise measurements. The discussion on the whole showed that, as M. Van Hamel said, society to defend itself must have an eye on every side. On Thursday the members of the Congress visited Sainte-Anne, where M. Magnan demonstrated the subject of degeneration. They also visited the Prefecture of Police, where M. Alphonse Bertillon showed his anthropometrical method of identifying criminals in action, and M. Moleschott succeeded with little trouble in identifying a man who had given a false name.