Just as little is known at present about the brain of criminals as about the skull. Some years ago Professor Benedict startled the world by stating that he had discovered the seat of crime in the convolutions of the brain. He found a certain number of anomalies in the convolutions of the frontal lobes, and he came to the conclusion that crime was connected with the existence of these anomalies. But he had omitted to examine the frontal convolutions of honest people. When this was done by other investigators, it was found that the brain convolutions of normal men presented just as many anomalies, some investigators (Dr. Giacomini) said even more than the brains of criminals. According to Dr. Bardeleben, there is no such thing as a normal type of brain. Weight of brain is a much simpler question than brain type, but so far it is impossible to say whether the criminal brain is heavier or lighter than the ordinary brain. The solution of this comparatively simple point is beset by a certain number of obstacles. It is not enough, Dr. Binswanger tells us, to weigh the brains of criminals and the brains of ordinary persons and then strike an average of the results. The height and weight of the persons whose brains are averaged are essential to the formation of accurate conclusions; till these important factors are taken into account, all deductions based upon weight of brain only rest upon an unsure foundation. But supposing we had a trustworthy body of facts bearing upon the weight and structure of the criminal brain, we should still require to know much more of brain functions in general before satisfactory conclusions could be drawn from these facts. We know something, it is true, of the physiological functions at certain cerebral regions, but as yet nothing is known of the localisation of any particular mental faculty, whether criminal or otherwise. A conclusive proof that the study of the brain, as an organ of thought, is still in its infancy, is found in the fact that the fundamental question is still unsolved, whether the whole brain is to be considered one in all its parts, so far as the performance of psychic functions is concerned, or whether these functions are localised in certain definite centres. Till these fundamental difficulties are cleared away, the presence of anomalies in certain convolutions of the brain will not prove very much one way or the other.[35] [35] A masterly article on the "Localisation of Brain Functions" will be found in Wundt's _Philosophische Studien Sechster Band_, 1. _Heft Zur Frage der Localisation der Grosshirnfunctionen_, Von W. Wundt. Compare also _The Croonian Lectures on Cerebral Localisation_, by David Ferrier. London: 1890.