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Summary. — The first part of this study (published in the fascicule 2, 1977, of the Revue de Géographie Alpine) described the glacier retreat of these last years and the morphological evolution that go with it ; the rock-glaciers are certainly the remains of different glacier retreats. But the Vallon de la Rocheure also presents a collection very complete of periglacial forms and microforms that show the present activity of physical processes as to solufluxion, vertical and horizontal selection of rock fragments, particularly between 3 000 and 2 600 m. This space seems to be the more frequently submitted to cycles frost- thaw. Above, snow and ice are the principal factors of the morphological evolution ; under, the vegetation partly protects slopes.

Summary. — The high-altitude alpine karsts of this area have a cold and hypersnowy climate. Consequently, it exists an important corrosion in spite of the feeble aggressivity of melting waters (lack of CO2). The actual sub-glacial karsts and the large « glacio-karst » depressions prove interaction between glacial « quarrying », absorption and dissolution. Caves are characterized by a vadose outflow and a rapid draining. Greatest karst landforms date probably from Ancient Quaternary while minor solutions forms are holocene.