ABSTRACT
Variations of nucleotide composition and frequency of CpG and CpNpG sequences in the clusters of nuclear ribosomal genes of taxa, belonging to two phylogenetic branches of Angiospermae have been statistically analyzed. This region of eucaryotic genomes is nucleolus organizer and functions in a separate compartment of cell nucleus that can do running here processes it is enough specific. It is shown that level of evolution advance of a taxon, defined on morphological data, is in positive correlation with quantitative value of dC, CpG and CpNpG. This is found in contradiction with beliefs about the general rules of the transformation of nucleotide composition in evolution, that suggest a CpG suppression. Cryptaffinous taxa being connecting link between a well morphological outlined taxonomic group, differ to be raised in
