In the gynoecium of <em>Dracaena fragrans</em>, <em>Sansevieria</em> <em>parva </em>and <em>S. trifasciata</em>, the vertical zonality of the ovary, the structural zonality of the gynoecium following Leinfellner, and the zonality of the septal nectary were studied. The ovary structure is characterised by a high parenchymatous ovary base and ovary roof as well as a long septal nectary that can be extended in both of them and opens with secretory nectary splits. The gynoecium of these species has a short synascidiate zone, a fertile hemisynascidiate zone with a median ovule attached, a hemisymlicate zone (only in <em>D. fragrans</em>) and an asymplicate zone (with postgenitally fused carpels) that comprises the ovary roof, common style and stigma. In the septal nectary, we detected three vertical zones: the basal zone of the distinct nectary in the ovary base or/and the synascidiate zone, the zone of the common nectary (in the hemisynascidiate and hemisymlicate zones) and the zone of the external nectary (the nectary splits in the asymplicate zone). The gynoecium structure in the studied species shows differences in the length of the gynoecium and septal nectary zones and also in the interrelationships of all these three types of vertical zonality.

The general morphology and micromorphology of the flower in Polygonatum multiflorum, Maianthemum bifolium, and Convallaria majalis were studied using light microscopy methods. Among the studied species, P. multiflorum and C. majalis have syntepalous and trimerous flowers, and in M. bifolium flowers are the most reduced: they are dimerous, pentacyclic, and with free tepals. Only in P. multiflorum stamens are considerably adnate to the floral tube. The gynoecium of P. multiflorum consists of synascidiate, hemisymplicate, and asymplicate zones. In the gynoecium of M. bifolium and C. majalis, synascidiate, symplicate, and asymplicate vertical zones were revealed. In P. multiflorum and M. bifolium, the style is composed of postgenitally connated carpels, while in C. majalis the style is formed by congenitally fused carpels (symplicate gynoecium zone). A common pattern of the venation of the floral parts was revealed in all the species.The external flower morphology and the gynoecium inner structure are different in all three species, providing adaptations for the pollination mode. Attractive elements observed in the flower of P. multiflorum are the long septal nectary in the ovary and epidermal trichomes on the inner perigonium surface and on the filaments. In M. bifolium, a rudimentary external septal nectary was observed for the first time. No nectaries or other morphologically distinct secretory structures were found in the C. majalis flower, allowing considering the C. majalis flowers as pollen flowers.

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We studied the structure of flowers of Galanthus nivalis and Leucojum vernum using cross-sections and longitudal sections of permanent preparations using a light microscope. Genera Galanthus and Leucojum belong to the Galantheae tribe characterized by a unique combination of features of the family Amaryllidaceae, i.e. absence of septal nectaries, poricidal anthers and fruit – fleshy capsule. Both species are represented in the flora of Ukraine and have the life form of bulb ephemeroid of decidous forests. Microscopic surveys of flowers are considered as an instrument for determining yet unknown structural adaptations of plants to specialized ways of pollination and determining the first stages of morphogenesis of fruit, because many features of the fruit appear already at the stage of flower. We determined that the tepals of both studied species have multi-bundle traces of 8–9 vascular bundles. Apical dehiscence of the anthers occurs due to short longitudinal sutures in the upper part of the anthers. The nectar disk on the roof of the inferior ovary is poorly differentiated, and has no vascular bundles. We associate the indicated peculiarities of the flower structure with the offer of pollen as the main reward of the pollinator during buzz-polination, which has not reported for the studied species. Placentation is axile in the lower part of the ovary and parietal in the upper one. We consider that the gynoecium of the studied species is eusyncarpous. The vascular system of the inferior ovary is composed of three dorsal and three septal veins, paired ventral bundles of carpels, which form the traces of ovules, and also small additional bundles in the wall of the ovary. For the first time, we have determined the presence of airy parenchyma in the ovules, ovary roof, the style and anthers’ connectives and have confirmed their presence in the tepals and the wall of the ovary at the stage of flowering. We found differentiation of the mesocarp into photosynthesizing and airy parenchyma, small sizes of cells of the endocardium in the area of the dorsal vein, bifurcate dorsal bundles of the carpels, which could be considered as adaptation of different stages of morphogenesis of fruit to dehiscence. Anatomical peculiarities of the ovaries of G. nivalis and L. vernum: numerous vascular bundles in the pericarp, thick parenchyma mesocarp with air-filled cavities, non-lignified endocarp at the stage of the flower we consider adaptations to the formation of fleshy fruit. The new data we obtained on the anatomical structure of the flowers is a significant addition of information about anthecological and carpological (post-anthetic) peculiarities of the surveyed species.

The structure of Agapanthus africanus and A. praecox flowers was studied on permanent cross-sectional and longitudinal sections using a light microscope. The genus Agapanthus belongs to the subfamily Agapanthoideae, the family Amaryllidaceae, which is characterized by the presence of the upper ovary, septal nectaries and fruit – fleshy capsule. Micromorphological studies of the flower are considered as a way for detection of unknown plant features, adjustment of plants to specialized ways of pollination and determining the first stages of morphogenesis of fruit, and further use these features in taxonomy. 10 flowers of A. africanus and A. praecox were sectioned using standard methods of Paraplast embedding and serial sectioning at 20 micron thickness. Sections were stained with Safranin and Astra Blau and mounted in Eukitt. It was found that in the studied species the tepals have single-bundle traces. The vascular system of the superior ovary consists of a three bundle dorsal vein, of the ventral roots complex, which are reorganized into paired ventral bundles of the carpel, which form traces to ovules. For the first time, the following gynoecium zones were detected in A. africanus: a synascidiate structural zone with a height of about 560 μm and a fertile symplicate structural zone with a height of about 380 μm and a hemisymplicate zone of 2580 μm. In A. praecox gynoecium, there is a synascidiate structural zone with a height of 200 μm and a symplicate structural zone of 600 μm and a hemisymplicate zone of 620 μm. Septal nectaries appear in the hemisymplicate zone and open with nectar fissures at the base of the column, with a total septal nectar height of 2880 μm in A. africanus and 820 μm in A. praecox. The ovary roof is 300 µm in A. africanus and 200 µm in A. praecox. Triple dorsal bundles of carpels in A. africanus have been identified, which could be considered as adaptation of different stages of morphogenesis of fruit to dehiscence. The new data obtained by the vascular anatomy of the flower and the presence of different ovary zones significantly add to the information about anatomical and morphological features of the studied species, which can be further used in the taxonomy of the family Amaryllidaceae.