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A radiocarbon-dated sequence at Gemenos, near Marseille, has provided Pleniglacial and Holocene molluscan assemblages. The Pleniglacial succession shows only small specific changes within a malacofauna, in the main, common in periglacial deposits of south-eastern France. In the Middle Pleniglacial part of the sequence, a colluvial level dated to 38,690 +/- 790 BP probably corresponds to a minor climate improvement during the marine isotopic stage (MIS) 3, potentially one of the oscillations of the Moershoofd-Pile interstadial complex. A deterioration then leads to loess accumulation with assemblages typical of cold open environments. A layer dated to 32,230 +/- 490 BP appears to be only marked by an increase of humidity. It could be related to the Hengelo-Charbon interstadial. This is followed by a non-dated arid and cold phase characterized by aeolian sands that contain a very poor fauna. It may represent an undefined event in MIS 2. The subsequent warming phase is not dated, but its assemblages, in which both cold tolerant and thermophilous species can be found, are representative of the Early Holocene between 10,000 and 9,000 BP. Finally, the last levels of the sequence contain Late Holocene assemblages (ca. 4,000 BP) including several synanthropic Mediterranean snails. The present findings contradict the assumptions that the open-country snail Pupilla muscorum (which today is rather hygrophilous in the Mediterranean area) is not to be found in the loess of Provence, and that there is a climate-related biogeographic gradient within the malacofauna of the "Wurmian" loess in south-eastern France with more xerophilic and Mediterranean assemblages near the littoral. A comparison with other MIS 3 land snail assemblages in Provence suggests a more complex regional pattern which remains difficult to comprehend owing to the lack of dated and well developed sequences in the different sub-regions of south-eastern France.