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The needles of 17 samples representing 15 populations of Pinus mugo Turra from the Alps, Apennines, Sudethians, Carpathians and Rhodopes were analysed in respect to 15 morphological and anatomical characters. The results of measurements were analysed statistically. The variation of the samples was generally not to large. Populations from the East Carpathians appeared different from all other examined. Two formed groups of analysed populations are separated mainly by thickness of epidermal cells, width/thickness of epidermal cell ratio, needle width and needle thickness. The differences between two groups of populations suggest their longer separation during Pleistocene.
A new subspecies of the Bulbophyllum tahitense (Orchidaceae), from The Society Islands (French Polynesia) is proposed. A new subspecies is described and illustrated. Keys to taxa of Society Islands genus Bulbophyllum, is added.
This paper presents the results of the study on morphological differentiation of seeds of five Polish species of the genus Sorbus L. (S. aria (L.) Crantz, S. aucuparia L. Emend. Hedl., S. chamaemespilus (L.) Crantz, S. intermedia (Ehrh.) Pers. and S. torminalis (L.) Crantz). The biometric data of 1980 seeds were subjected to multivariate statistical analysis in attempt to define intraspecific variation and to find differences between studied taxa. Most of the seed traits are significantly correlated and are characterised by moderate level of variation. Seeds of S. aucuparia (both subspecies) are the least variable while seeds of S. torminalis and S. intermedia the most. On the basis of size and shape traits of Sorbus seeds only seeds of S. aucuparia can be definitely distinguished from the others.
The characteristic of Pinus uncinata on the basis of biometrical analyses of 16 cone features was done. The research was based on 8 samples representing 6 populations, consisting of 50 cones each, collected in the Pyrenees, within the natural range of the species. All the investigated cone features were moderately differentiated, with the variation coefficient ranging from 8 to 30%. The particular populations differ significantly from each other statistically according to several features examined. The samples collected in the same population also vary significantly. The differences between populations, however, do not enable their division into groups, which supports their origination from the same Pleistocene refugia.
The intra- and inter-population variation in three populations of Juniperus excelsa, two from Crimea and one from the Balkan Peninsula, were analyzed biometrically. Fourteen morphological characters of cones, seeds, shoots and leaves were used. The number of seeds per cone appears to be the most variable character. The others were more stable. Differences among particular individuals within the samples were slight, as well as between populations compared. The Crimean samples were very close to each other, while the more geographically distant sample from the Balkan Peninsula appears also to be morphologically more separate. This suggests that the Balkan populations originated from another Pleistocene refugium. The Crimean populations did not show the reduction of variability, which could have resulted from their geographical isolation and their considerably restricted numbers of individuals.
Information on Potamogeton hybrids, their identification, taxonomy, ecology and distribution has not been sufficiently recognised yet. Based on characters of P. x salicifolius (= P. perfoliatus x P. lucens) from a new locality in Poland - the Gatno lake (the Kaszuby Lakeland in NW Poland) - general comments on Potamogeton hybrids identification are introduced. The description of P. x salicifolius morphology from the Gatno lake are presented. Analysis of quantitative morphological characters of these specimens provided new information on variability of this taxon. The distribution map of P. x salicifolius in Poland, the original draft of P. x salicifolius based on specimens from the Gatno lake and the table with comparison of P. x salicifolius and the characters of parental species are also provided.
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