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No lacustrine and bog deposits of Eemian=Mikulino age have been found in the southern Russian Plain. During Mikulino epoch the Dniester, middle and lower Dnieper, Don, upper Oka, middle Kuma River basins and other regions with loess-paleosoil formation (LPF) were subjected to accumulation of fossil soils, loess horizons, and alluvial deposits. The author's reconstructions of landscapes and climate for Eemian and other thermochrons and cryochrons of the Late and Middle Pleistocene were based on detailed palynologic analysis and complex (lithological, paleopedological, microteriological, etc.) investigation of reference sections of the main loess stratoregions. The upper Don region is situated within the zone of Don=Helmian=Glacial C moraine spreading. Complete Pleistocene sequence is preserved in Strelitsa reference section. Mikulino interglacial in this section is represented by Salyn soil formed on the Dnieper loess and part of Krutitsk soil overlying it. Both soils form Mezin soil complex. Subhorizon A11 of the Krutitsk soil corresponds to the Early Valdai cooling and subsequent interstadial. Forest steppes predominated throughout the whole interglacial. Only forest formations underwent cardinal transformations (9 succession phases) during this epoch. The Middle Desna region is situated within the area covered by the Dnieper=Saalian ice cap. In the Arapovichi section the Dnieper moraine is overlain by 14-m thick Late Pleistocene loess-soil formation. According to palynostratigraphical evidence, the author considers Mikulino interglacial to be represented here by sands and loams overlying the moraine together with superposed Salyn soil and the lowermost part of sod-chernozem Krutitsk soil. Eleven phases in evolution of the forest vegetation have been established for this thermochron. Palynologic study of the sections situated in the extra-glacial region (Moldova I and V, Korman', Ketrosy, etc.) allowed N.S. Bolikhovskaya and G.A. Pashkevich to describe Mikulino interglacial and 19 Valdai (9 interstadials and 10 stadials) stages in evolution of flora, vegetation, and climate of the Middle Near Dniester region. A soil complex exposed in Moldova I section at the depth of 20 m was accumulated during Mikulino epoch. The complex consists of two brown forest soils with loess layer separating them. We have outlined seven alternating phases in evolution of the predominant forest steppe vegetation during this interglacial. Several climatic-stratigraphical subdivisions were established within the Eemian=Mikulino climate rhythm. Of these are: thermoxerotic and thermohygrotic stages, substages, and endothermal coolings (Bolikhovskaya, 1981, 1993). The main endothermal was recorded between the mentioned stages in Moldova I, Arapovichi, and Strelitsa sections. Another endothermal was established in the first half of the interglacial (Arapovichi). The complicated structure of the Eemian=Mikulino interglacial is confirmed by the data on Bispingen section (Field et al., 1993). Among glacial stages in evolution of LSF of the Russian Plain the most complicated climatorhythmics is typical of the Valdai glacial. It is characterized by 10 stadials, 9 interstadials, and several interphases. When studying Late Pleistocene sequences of extra-glacial regions, one must take into account the fact that we have reconstructed landscape-climatic situations resembling interglacials for Ketrosy (first Early Valdai) interstadial in middle Desna region, and Kishlyany (second Early Valdai) and Dniester (third Middle Valdai) interstadials in the middle Dniester region. The report deals with peculiarities of phytocoenotic and climatic successions and composition of characteristic taxa of the Eemian=Mikulino interglacial in the three the most typical stratoregions.