XVI International Botanical Congess

New data on the morphology, anatomy, onto- and organogeny in Ranunculaceae are obtained. The grounds for considering Ranunculaceae to be a taxon in which all basic directions of somatic evolution are displayed. Oligoxylity of the studied family should be considered to be the main factor determining the structural diversity and high evolutionary potentials of Ranunculaceae. Traits of morphological and anatomical organization, shared by Ranunculaceae and monocotyledons are thought to be a result of convergence. Basic tendencies and transformation modes of onto-, organo- and histogenesis in the process of structural evolution are revealed. The concept of a shoot elementary metamere?s morphogenetic significance for the formation of biomorphs was substantiated. The unity of origin of axial and appendicular organs in flowering plants was confirmed from a principally new standpoint.