It is even more difficult to come to a satisfactory conclusion with regard to European examples of the practice we have been describing. Trepanation was certainly practised in the treatment of certain diseases of the bone, such as osteitis or caries. Professor Parrot mentions a case worth quoting.30 A few years ago several skeletons were found at Bray-sur-Seine (Seine-et-Marne) with numerous objects, such as polished stone hatchets, bone stilettos, shell necklaces and ornaments, all undoubtedly Neolithic. One of the crania had been trepanned, the position of the operation showing that its object had been to treat an osteitis. The operation had succeeded, and the cicatrization of the bones, both about the wound and in the parts originally affected, shows that recovery was complete. This is the only example we have of an operation executed with a view to curing a disease that can actually be seen, and it enables us to conclude that these men, of whom we know so little, had some notion of surgery. Were trepanations also practised to cure epilepsy or to heal mental affections? From the earliest times the seat of these troubles was always supposed to be the brain, and an ancient book of medicine recommends as a remedy the scraping of the outside of the skull.31 In a recent book (“De la Trépanation dans l’Épilepsie par le Traumatisme du Crâne”), Echeverria mentions several cases of cure by trepanation when epilepsy had been the result of an injury. Observation may have led our prehistoric ancestors to discover this. May we date this custom then from prehistoric times? It is very difficult to decide with certainty either for or against it. Of one thing, however, we may be quite certain. The cranial perforations so much like one another reported from districts so remote and different in character, cannot be accidental. It is impossible to attribute to chance the occurrence of injuries of exactly the same size in crania of totally different origins. Setting aside the Entre-Roches skull, the antiquity of which does not seem to us sufficiently established, we find this custom maintained throughout the period characterized by the use of polished stone weapons and implements, the erection of megalithic monuments, and the domestication of animals. It was practised by the men of the cave of _L’Homme Mort_ at the beginning of the Neolithic period, and was still in use at Moret when metals began to be known. The discoveries of Dr. Wankel, the excavations of the tumulus of Guisseny, prove that trepanation was continued throughout the Bronze age, whilst the Jeuilly and Limet tombs show that it was not discontinued even in Merovingian times.