- 4 - Approximately the same zonation occurred in the upper Pliocene-Pleistocene; judging from the travertine floras found at the altitudes of 600 and 2200 m, the upper forest zone was also represented by beech - fir forests, and the lower mountain zone - by the forests of Quercus iberica. The study of older Miocene and Pliocene floras of Colchis also confirms the existence of the mountain vegetational zonation at that time. From Sarmation to Cimmerian, inclusive, the flora and vegetation were different, although the general forest character of the country was the same. In the lower belt, typically subtropical forests were developed with the prevalence of evergreen trees and shrubs, including lianas. The laurels were particularly numerous (Aniba, Daphnogenia, Laurus, Lindera, Ocotes, Persea). In the middle Pliocene the sclerophyllous oak forest formations were widely spread in the same belt. However, by the post - Cimmerian period the altitudinal range of this belt sharply decreased; all the thermophilous subtropical species became extinct. The belt of warm - temperate forest shifted down to sea level, while that of temperate beech and fir forests extended its area. About that time witnessed the formation of alpine, treeless vegetation. The forest-forming species of almost all those forest belts (especially the upper ones) in the epochs considered belonged, approximately, to the same genera as now, but the species composition underwent considerable changes in the later Neogene. Thus, e.g., Fagus attenuata Goepp. was replaced by F.orientalis. The composition of fir species also changed: Abies firma Sieb. et Zucc. fossilis in the Miocene, A.cilicica Carr.fossilis in the middle Pliocene, and from the end of the Pliocene to the present time - A.nordmanniana. The species of Carpinus were also different: C.colchica Kolak., C.subcordata Nath. and C.subjedcensis Konno - in the Sarmatian, C.cuspides (Sap.) Kolak., C. pliofaueri Rat. and C.uniserrata (Kolak.) Rat. in the Pontian, C.betulus s.l. and C.orientalis in the Pleistocene - Holocene. The change in Quercus species was particularly striking. Especially characteristic for the Middle Pliocene were the species from the Cerris section: Quercus cerris-fossilis Kolak., Q. kubi