Аннотация:The levels of morphological differences in the flower structure have been ascertained. The majority of deviations from a typical variant are determined only on a genetic level. And the plants which have these deviations can be separated into their own systematic categories. Deviations from a typical variant of a flower structure of other plants take place in the process of ontogenesis (for instance, nectaria reduction, flower symmetry change); and it is determined not only on a genetic level but also as a result of a long evolutionary geographical isolation from relative species and genera, and because of the reasons of ecological adaptation. As a consequence there is difficulty of systematics of the later taxons.