Results 151 to 160 of about 692 (179)

Evolutionary trends in Winteraceae pollen

Grana, 2002
The Winteraceae, being considered as one of the most basal angiosperm families, has been extensively studied palynologically. The present study reviews the characters dispersal unit (monad versus tetrad) and size of the lumina in the tectum in the light of recent molecular research.
Raymond Van der Ham, Bertie Joan van Heuven   +1 more
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Anatomy of the Secondary Phloem in Winteraceae

IAWA Journal, 1984
The secondary phloem of nine species in five genera of Winteraceae was examined with regard to features that could serve for taxonomic and phylogenetic evaluation of the family. The species examined were as follows: Bubbia pauciflora, B. semecarpoides, Drimys lanceolata, D.
Katherine Esau, Vernon I. Cheadle
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TAXONOMY IN WINTERACEAE

TAXON, 1988
SummaryAfter a review of a number of characters of the Winteraceae, two topics are discussed. Firstly, it is argued that determination factors of place, size, form, and function of petals and stamens can become unlocked and fixed again in a different way, giving rise to a new form: the stamen with a petaloid appendage, which consequently has to be ...
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Analysis of the Contents of Oil Cells in Tasmannia lanceolata(Poir.) A. C. Smith (Winteraceae)

Annals of Botany, 2000
The simple, robust oil cells found in leaves of Tasmannia lanceolata (Poir.) A. C. Smith (Winteraceae) are shown to contain a preponderance of the bioactive compound polygodial using both direct sampling and GCMS analysis of cell contents and Fourier ...
Read, CD (15775268), Robert Menary (14744206)   +1 more
exaly   +1 more source

Placentation in Exospermum stipitatum (Winteraceae)

Botanical Gazette, 1978
Exospermum, of the primitive vesselless angiosperm family Winteraceae, has been described as differing from other genera in the family in having ovules scattered over the internal walls of the carpels. Studies of developing carpels with the scanning electron microscope revealed that ovules are initiated in a single row on each of the two placentas, as ...
F. B. Sampson, Shirley C. Tucker
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Chloroplast evidence for geographic stasis of the Australian bird-dispersed shrub Tasmannia lanceolata (Winteraceae)

Molecular Ecology, 2010
Few chloroplast-based genetic studies have been undertaken for plants of mesic temperate forests in the southern hemisphere and fossil-based models have provided evidence of vegetation history only at the broadest scales in this region.
James R P Worth, Gregory J Jordan, Gay E Mckinnon   +2 more
exaly   +2 more sources

A Winteraceae pollen tetrad from the early Paleocene of western Greenland, and the fossil record of Winteraceae in Laurasia and Gondwana

Journal of Biogeography, 2017
AbstractAimWinteraceae comprise c. 130 species in seven genera, with the greatest species diversity in the Pacific (Pseudowintera, Zygogynum), Australia (Bubbia, Tasmannia), New Guinea (Belliolum, Bubbia, Zygogynum, Tasmannia) and Madagascar (Takhtajania). Only Drimys occurs in South America. Because of their Cretaceous leaves, wood and pollen fossils,
Friðgeir Grímsson, Guido W. Grimm, Alastair J. Potts, Reinhard Zetter, Susanne S. Renner   +4 more
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An Ultrastructural Study of the Phloem of Drimys (Winteraceae)

IAWA Journal, 1985
The ultrastructural features of mainly primary phloem of three species of Drimys (Winteraceae), D. winteri J. R. ' G. Forst., D. lanceolata (Poiret) Baill. and D. granadensis L. f. var. mexicana (DC.) A. C. Smith are similar to those usually observed in dicotyledons.
Jennifer Thorsch, Katherine Esau
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A RECONSIDERATION OF THE GENUS TASMANNIA (WINTERACEAE)

TAXON, 1969
SummaryNew chromosome counts based on collections of Winteraceae have strengthened the conclusion, suggested by morphological and anatomical study, that the two Sections (Tasmannia and Drimys) traditionally treated in the genus Drimys J. R. & G. Forst. are very distinct and merit full generic status. Consequently Tasmannia R. Br. ex DC. is herewith
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Carpel Development in Tasmannia insipida (Winteraceae)

International Journal of Plant Sciences, 1996
Angiosperm carpels are closed (sometimes barely so) saclike structures, sometimes with a long ventral stigmatic crest. Interpretation of winteraceous carpels, particularly those of Tasmannia (synonym Drimys sect Tasmannia) piperita, has been critical to both ontogenetic and phylogenetic theories regarding general carpel development.
openaire   +1 more source