The empirical data on the variations in the Pleistocene natural environment obtained on the basis of the paleoclimatic records of the deep-sea and continental sections are analyzed in order to reveal the climatic cyclicity related to the 400 k.y. component of variations in the eccentricity of the Earth’s orbit in these data. It is indicated that the 400 k.y. cycle is almost unobserved in the records of paleoclimatic parameters directly reflecting climatic variations in the Pleistocene in the deep-sea and continental sections. The reports that the 400 k.y. cyclicity is present in the Pleistocene records of variations in the natural environment are mostly intrinsically contradictory. The absence of this eccentricity cyclicity in paleoclimatic records of the Pleistocene can confirm the mid-Pleistocene transition mechanism previously proposed by V.A. Bol’shakov.