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The monumental park in Mikuszewo near Miłosław covers the area of 3.95 ha. The park and the herbal plant communities, which can be observed recently, are relicts of a complex realised in last years of 19th century. The dendroflora contains 30 species of trees and shrubs. The most interesting element are numerous, large and picturesque trees of Acer campestre – the species, which is native, but relatively rare in Poland. An old tree of Gymnocladus dioicus – interesting exotic species – grows also in central part of the park.
The paper presents in the first time the results of a micromorphological study on stamens of Sansevieria species. Flowers of 15 species obtained from herbarium specimens deposited at the Royal Botanic Gardens, Kew, the Botanical Garden Berlin-Dahlem and the Botanical Garden in Poznań were studied. Observations were conducted under a light and a scanning electron microscope. The study revealed significant differences between the outer and inner surfaces of anthers. All species have a well-defined endothecium of enlarged cells with a U-shaped or helical secondary wall thickening. The article includes descriptions and illustrations of several quantitative and qualitative features of anthers and filaments of some Sansevieria species. Our study indicates that stamen micromorphology may be taxonomically significant.
The following paper presents the results of observations of the size and condition of cheddar pink (Dianthus gratianopolitanus Vill.) population in the “Goździk siny w Grzybnie” reserve (Wielkopolska Province), as well as active cultivation of the species in ex situ controlled conditions and its reestablishment supporting the natural, endangered population in the reserve.
The type and distribution (locations) of calcium oxalate crystals in mature leaves of 19 taxa of Philodendron (subgenera Meconostigma, Pteromischum and Philodendron) were studied. The calcium oxalate crystals were mainly found in the form of raphides, druses, styloids and prisms. The leaves of Philodendron demonstrate the presence of five distinctive raphide crystal types (biforine, thin-walled spindle-shaped, wide cells containing a wide raphide bundle, bundles of obliquely overlapping crystal and unmodified cells with either a single crystal needle or their cluster). Styloids and druses were found in all taxa at varying frequencies. Simple prisms and variations in crystal forms were most frequently observed in the ground tissue in petioles and midribs. This study represents additional data concerning calcium oxalate crystals in Philodendron.
A comparative morphological and anatomical study on the petioles and lamina of 22 taxa (species, subspecies and cultivars) of the genus Philodendron (subgenera Meconostigma, Pteromischum and Philodendron) has been made in order to investigate interspecific differences which may be useful in species identification. All species have bifacial leaves with petioles, amphistomatic with a strongly reduced density of stomata on the adaxial leaf surface. The species differ in the size and shape of their epidermal cells, the distribution and types of stomata and cuticle ornamentation in the lamina, thickness of epicuticular layer, presence or absence of hypodermis, structure of spongy mesophyll, thickness of palisade and spongy mesophyll layers, as well as types of raphides, and in the structure and forms of petioles. A combination of these characters may be useful in species identification. This study shows that there is some variation in petiole and leaf morphological and anatomical characters among the 22 taxa of Philodendron. However, many characters are present in all of them and may be typical of the genus. The study revealed several detailed interesting epidermal and anatomical features that have not previously been reported in the genus.
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