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Science 18 February 1972:
Vol. 175. no. 4023, pp. 772 - 774
DOI: 10.1126/science.175.4023.772
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Articles

Evidence of Pollen Tubes in Paleozoic Pteridosperms

Gar W. Rothwell 1

1 Department of Botany, University of Alberta, Edmonton 7, Alberta, Canada

A saccate pollen grain with a branched pollen tube has been discovered within the pollen chamber of a fossil seed-fern ovule of Middle Pennsylvanian age. This suggests that microgametophytes comparable to those of living gymnosperms were produced by some Paleozoic pteridosperms.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Evidence of Paleozoic Chromosomes from Lycopod Microgametophytes.
S. D. Brack-Hanes, S. D. BRACK-HANES, and J. C. VAUGHN (1978)
Science 200, 1383-1385
   Abstract »    PDF »
Evidence for a Pollination-Drop Mechanism in Paleozoic Pteridosperms.
G. W. Rothwell and G. W. ROTHWELL (1977)
Science 198, 1251-1252
   Abstract »    PDF »


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Science. ISSN 0036-8075 (print), 1095-9203 (online)