The Rock Shelter situated on the Middle Terrace at Le Moustier was excavated by Lartet and Christy in 1863, and yielded a series of implements of a special culture to which de Mortillet gave the name of Le Moustier. This industry, which to the early prehistorians seemed relatively simple, with the side-scraper and point as its typical implements, has now shown itself to be complex, owing to the discovery of new sites of Le Moustier date, very widely distributed geographically, and to the careful re-examination of the classical site itself. The Abri classique on the Middle Terrace at Le Moustier has been the subject of subsequent excavations by Bourlon, Chastaing, Hauser and Peyrony. The deposits in the Lower Terrace have also been examined by Rivière and Hauser. It was here that in 1908 the latter discovered the skeleton of Neanderthal type now in the Berlin Museum. In 1910 the Rock Shelter on the Middle Terrace, together with the Lower Terrace, was purchased by the French Government, and, subsequent to this, Peyrony has carried out on the Lower Terrace the admirable series of excavations, which he has carefully described in a recent publication. The present paper deals briefly with the morphology of the implements from the various layers as determined by Peyrony, and applies the statistical methods developed by the author to the discrimination of the various layers and the correlation of the implements from the Middle and Lower Terraces.