Typhaceae
Perennial, palustrial or aquatic herbs with a creeping rhizome; stems erect, solid, submerged at the base. Leaves biseriate, partly radical or subradical, partly cauline, lower congested, higher remote, elongate-linear, rather thick and spongy, bluntmargined; their sheathing bases excreting slime on...
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Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
1948
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Subjects: | |
Online Access: | http://www.repository.naturalis.nl/record/532543 http://www.repository.naturalis.nl/document/570370 |
Summary: | Perennial, palustrial or aquatic herbs with a creeping rhizome; stems erect, solid, submerged at the base. Leaves biseriate, partly radical or subradical, partly cauline, lower congested, higher remote, elongate-linear, rather thick and spongy, bluntmargined; their sheathing bases excreting slime on their inner side. Flowers very numerous, very closely packed in 2 or less often 3, superposed, contiguous or more or less remote terete unisexual spikes; upper spike male; the 1-2 lower ♀; all spikes at the base with a foliaceous bract which falls off long before anthesis; the ♀ spikes here and there between the flowers often with a similar bract. ♂ Flowers consisting of 3 flat hairs together surrounding 2-5 stamens; anthers basifixed, linear, 2-celled; connective shortly produced; cells back to back, bursting longitudinally; pollengrains free or cohering in tetrads. Rachis of ♀ spathe closely studded with patent cylindrical thickish excrescences; between these excrescences and on their basal part beset with flowers containing a fertile ovary; higher part of the excrescences bearing rudimentary ovaries. ♀ Flowers with or without a very narrow bracteole; bracteole with a more or less broadened, often dentate-acuminate apex either entirely hidden by the flowers or their apex visible externally. Ovary borne by a long very thin stalk (gynophore) which bears long hairs on its base, fusiform, 1- celled; style distinct thin; stigma broadened, unilateral, linear or spathulate. Fruit small, fusiform, or elongate-ovoid, falling off together with its stalk from the pilose axis of the spike, finally bursting by a longitudinal slit; seed pendulous, striate; endosperm mealy; embryo narrow, straight, nearly as long as the seed. Distr. Throughout the world between the arctic circle and lat. 35 S, comprising ± 7 spp., in Malaysia only one very variable species. |
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