WANG, XIN* AND DAVID DILCHER. Paleobotany Lab, Florida Museum of Natural History, University of Florida, Gainesville, FL32611-7800. - Study of Ternstroemites Leaves and Their Relationships With Living Gordonia.
Ternstroemites leaves are frequently found in Eocene Claiborne
age clay deposits in Western Kentucky and Tennessee. The present study
was focused upon anatomical and morphological analysis of the fossil
leaf Ternstroemites and leaves of the living plant,
Gordonia lasianthus . This analysis consists of leaf form, size,
margin, venation, cuticle characters (including stomata, trichomes and
epidermal cells) of the fossil and modern leaves. Reports of
Gordonia have been made based upon fruits and seeds preserved
in the same clay deposits from which Ternstroemites leaves
have been found. Therefore we applied a rigorous comparison of leaf
characters to see if the fossil leaves also demonstrate close
similarities of numerous characters to the living genus
Gordonia. The character sets of the fossil and living leaves
appear similar. As a result of its ancient history, Gordonia is
distributed today Southeast Asia, southeast North America, Central
America and north South America. Changes in paleoatmosphere
concentration of carbon dioxide can also be observed from the stomatal
index data of the fossil leaves.
Key words: Claiborne, Eocene, Gordonia, Ternstroemites, Theaceae