Was there any abrupt transition from one period to another? Must we accept the theory of a long break caused by geological phenomena, and the temporary depopulation which was one of the consequences of these phenomena? Did the new era of civilization date from the arrival of foreign races, stronger and better fitted than those they succeeded for the struggle for existence? Or are these changes merely the result of the natural progress which is one of the laws of our being? These questions cannot now be solved, and if the industries which are at the present moment the object of our researches, bear witness to the employment of a new process, that of polishing, we are bound to add that everywhere Paleolithic forms are still persistent. Flints, merely chipped, are clumsy tools, but there is no break in their series till we come to the splendid specimens from Scandinavia or from Mexico. Of the seven types of the Solutréen period, six are met with in the time now under consideration.7 Five types of Solutréen javelins have also been found in the Durfort Cave, and beneath the dolmens of Aveyron and of Lozère. Neolithic weapons, such as those found in the Moustier Cave, are not so numerous, but the type adopted there is not such a fine one nor so carefully finished, which accounts for its having been more rarely copied. If we examine the knives, awls, scrapers, and saws, we come to the same conclusion, although comparison is not so easy. “A knife is always a knife, an awl is always an awl,” remarks M. Cartailhac; “they were made at every period, and their resemblance to each other proves nothing with any certainty.” Rounded stones of granite or sandstone seem however to have been weapons peculiar to the Neolithic period. Dr. Pommerol recently spoke at the Anthropological Society of Paris, of two such rounded stones picked up in the Puy-de-Dôme. Similar stones have been discovered at Viry-Noureuil, and M. Massénat has one in his collection from Chez-Pourré. Are not these rounded stones of a similar character to the _bolas_ flung by the ancient Gauls, and still in use amongst the inhabitants of the pampas of South America?