KLAVINS, SHARON D.* AND LAWRENCE C. MATTEN. Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901-6509. - Elaboration of the anatomy and morphology of Wexfordia hookense, Matten.
Recently collected specimens of Wexfordia hookense, a lycopod
from the Uppermost Devonian of Hook Head, County Wexford, Ireland,
have revealed new data on its anatomy and morphology. The pyritized
and limonitized axes were prepared for examination by light microscope
and scanning electron microscope. Periderm and secondary xylem for
Wexfordia are described for the first time. Leaf anatomy
shows similarities to the leaves described for Phytokneme
rhodona Andrews, Read and Mamay from the Upper Devonian of
Kentucky. Scanning electron microscopy shows details of cell walls in
primary and secondary xylem. The range of ontogenetic states present
in the suite of specimens collected permits the proposal of a model of
Wexfordia's growth architecture.
Key words: anatomy, Devonian, lycopod, Wexfordia hookense