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

Published online by Cambridge University Press:  14 July 2015

Benton M. Stidd
Benton M. Stidd*
Affiliation:
Department of Biological Sciences, Western Illinois University, Macomb 61455
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Abstract

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.

Type
Research Article
Information
Journal of Paleontology , Volume 65 , Issue 1 , January 1991 , pp. 160 - 166
Copyright
Copyright © The Journal of Paleontology 

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References

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