Embryological character states are mapped on the diagrams of dicotyledons (G. Dahlgren 1989). The often well-defined pattern of distribution forms a basis for discussing and clarifying phylogenetic relations. It is shown how numerous embryological characters, alone or in combinations, support certain systematic constellations, even if the character states may have arisen independently within a varying number of evolutionary lines. Characters presented are: anther wall formation; tapetum types; cells in pollen grains at dispersal; microsporogenesis; ovule morphology; ovule integuments; endothelium; obturator; parietal tissue; embryo sac formation; antipodal cells; hypostase, embryogeny; polyembryony; endosperm formation; persistence of endosperm; ruminate endosperm; endosperm haustoria; perisperm; storage compounds in the endosperm; chlorophyllous embryo; embryo size, seed coat characters; arils; dry and wet stigma types.

DAHLGREN, C, 1989. An updated angiosperm classification. A new two‐dimensional diagram, reflecting the system of classification of the angiosperms, is presented. It combines the dicotyledon diagram in G. Dahlgren (1989) and an adapted monocotyledon diagram after that in Dahlgren (1985) in a single diagram. An updated monocotyledon taxonomy is presented and the classification is appended.

Dahlgren, G . 1993. Ranunculus penicillatus in Norden. -Nord. J. Bot. 13: 593-605. Copenhagen. ISSN 0107-05SX.Twenty-one populations of Ranunculus subgenus Batrachium (Ranunculaceae) from central Jutland, Denmark, were studied in the field and sampled for cytological, morphological and embryological investigation; for embryology the confocal laser scanning method (CLSM) was used. Six taxa were represented: R. penicillatus ssp. penicillatus and ssp. pseudojluitans, R. aquatilis var. aquatilis, R. peltatus ssp. peltatus and ssp. baudotii and R. circinatus. The main aim was to determine whether R. penicillatus occurs in the area. 14 of the 21 populations were referred to R. penicillatus; all 14 were tetraploid, though a few triploid plants were also found in two of these populations. Some populations show characteristic features of hybrid origin. These have, however, found a niche in swift rivers in west-central Jutland, reduction in fertility being compensated for by the dominant asexual mode of reproduction, and new parts of the river systems have continually been invaded. They are accorded taxonomic rank, the heterophyllous populations being treated as ssp. penicillatus and the homophyllous populations as ssp. pseudojluituns. Accordingly, R. penicillatus is represented in Denmark and thus in Norden. Flora Nordica Notes no. 7.

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