scholarly journals Telangiopsis Gen. Nov., an Upper Mississippian Pollen Organ from Arkansas

1971 ◽  
Vol 132 (1) ◽  
pp. 30-37 ◽  
Author(s):  
Donald A. Eggert ◽  
Thomas N. Taylor
Keyword(s):  
Pollen Organ

On a new medullosan pollen organ from the Pennsylvanian of North America

2006 ◽  
Vol 142 (3-4) ◽  
pp. 219-227 ◽  
Author(s):  
Rudolph Serbet ◽  
Thomas N. Taylor ◽  
Edith L. Taylor
Keyword(s):  
North America ◽  
Pollen Organ

scholarly journals Scanning Electron Microscopy and Synchrotron Radiation X-Ray Tomographic Microscopy of 330 Million Year Old Charcoalified Seed Fern Fertile Organs

2009 ◽  
Vol 15 (2) ◽  
pp. 166-173 ◽  
Author(s):  
Andrew C. Scott ◽  
Jean Galtier ◽  
Neil J. Gostling ◽  
Selena Y. Smith ◽  
Margaret E. Collinson ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Synchrotron Radiation ◽  
Materials Science ◽  
Single Specimen ◽  
X Ray ◽  
Swiss Light Source ◽  
Pollen Organ ◽  
Paul Scherrer ◽  
Scanning Electron

AbstractAbundant charcoalified seed fern (pteridosperm) pollen organs and ovules have been recovered from Late Viséan (Mississippian 330 Ma) limestones from Kingswood, Fife, Scotland. To overcome limitations of data collection from these tiny, sometimes unique, fossils, we have combined low vacuum scanning electron microscopy on uncoated specimens with backscatter detector and synchrotron radiation X-ray tomographic microscopy utilizing the Materials Science and TOMCAT beamlines at the Swiss Light Source of the Paul Scherrer Institut. In combination these techniques improve upon traditional cellulose acetate peel sectioning because they enable study of external morphology and internal anatomy in multiple planes of section on a single specimen that is retained intact. The pollen organMelissiothecashows a basal parenchymatous cushion bearing more than 100 sporangia on the distal face. Digital sections show the occurrence of pollen in some sporangia. The described ovule is new and has eight integumentary lobes that are covered in spirally arranged glandular hairs. Virtual longitudinal sections reveal the lobes are free above the pollen chamber. Results are applied in taxonomy and will subsequently contribute to our understanding of the former diversity and evolution of ovules, seeds, and pollen organs in the seed ferns, the first seed-bearing plants to conquer the land.

Saharatheca lobata n. gen. and sp.: a new medullosan (seed fern) pollen organ from the Middle Pennsylvanian of Illinois

1991 ◽  
Vol 65 (1) ◽  
pp. 160-166 ◽  
Author(s):  
Benton M. Stidd
Keyword(s):  
Vascular Supply ◽  
Outer Side ◽  
Ground Tissue ◽  
Southern Illinois ◽  
Fertile Frond ◽  
Pollen Organ ◽  
Pollen Sacs

Several specimens of a pollen organ containing Monoletes pollen occur in a single coal ball collected from the Herrin No. 6 Coal at the Sahara Coal Company Mine in southern Illinois. Specimens are 3–4 cm long, up to 1 cm wide, and are either bilobed or trilobed; 5–7 pollen sacs are arranged along each side of a discontinuously sclerified ground tissue plate extending into each lobe. The vascular supply from the peduncle breaks up by repeated dichotomies and one bundle descends along the outer side of each pollen sac. The mode of dehiscence and the structure of the tip of the organ remain unknown. Each lobe (and contained sporangia) is hypothesized to be derived from an ancestral fertile frond segment bearing pendulous sporangia.

SULLITHECA DACTYLIFERA GEN. ET SP. N.: A NEW MEDULLOSAN POLLEN ORGAN AND ITS EVOLUTIONARY SIGNIFICANCE

1977 ◽  
Vol 64 (8) ◽  
pp. 994-1002 ◽  
Author(s):  
Benton M. Stidd ◽  
Gilbert A. Leisman ◽  
Tom L. Phillips
Keyword(s):  
Evolutionary Significance ◽  
Pollen Organ

A reappraisal of the Dinantian floras at Oxroad Bay, East Lothian, Scotland. 1. Floristics and the development of whole-plant concepts

1990 ◽  
Vol 81 (2) ◽  
pp. 127-159 ◽  
Author(s):  
Richard M. Bateman ◽  
Gar W. Rothwell
Keyword(s):  
New Species ◽  
Distinct Species ◽  
Taxonomic Composition ◽  
Evolutionary Significance ◽  
Life Strategies ◽  
Whole Plant ◽  
Whole Plants ◽  
Pollen Organ ◽  
First Time ◽  
A New Species

ABSTRACTRe-investigation of species-rich late Tournaisian floras at Oxroad Bay reveals eight plant-bearing exposures that represent four distinct stratigraphic levels. The allochthonous megafossil assemblages vary in degrees of disarticulation, modes of preservation and taxonomic composition. Within-site stratigraphic distributions are presented for 43 anatomically-preserved organ-species; of these, 12 are new to science, 18 have not previously been recorded at the locality, 21 are illustrated from the locality for the first time and 19 are currently considered endemic. Another six have been recorded in error from unprovenanced water-worn blocks. Nineteen adpressed organ-species are also described. Methods and concepts of whole-plant reconstruction are reviewed. At least 11 whole-plant species occur at Oxroad Bay. The lycopsids comprise an enigmatic plant with anAsteroxylon-like stele and two morphologically- and ecologically-distinct species ofOxroadia. A new species ofProtocalamitesdemonstrates the earliest evidence of heterospory and tuberoid stem-bases in the sphenopsid clade.CladoxylonandStauropterisrepresent the pteropsids. At least five lyginopterid pteridosperm species are present. They include both trees (Eristophyton, Bilignea) and shrubs/pseudoherbs (e.g.Tetrastichiaand theTriradioxylon–Calathopteris–Oxroadopteris–‘Tristichia’ plexus), suggesting a range of life strategies. Their diversity has complicated attempts to reconstruct whole-plants, though attachment is demonstrated between several ovules and cupules, and several ovules and pollen-organs are correlated using shared microspores. Elements of particular evolutionary significance include the ‘megacupule’Calathospermumand a structurally similar pollen-organ aggregate, a bisexualPullarithecacupule, and a complete ontogenetic sequence ofHydraspermaovules. Comparable Dinantian floras are reviewed.

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