New observations on Sawdonia ornata from Scotland

1983/01/01 by R.J. Rayner · 1 citation
Earth and Planetary Sciences · Agricultural and Biological Sciences · #Paleontology and Stratigraphy of Fossils #Plant Diversity and Evolution #Geological formations and processes #Biology #Devonian #Xylem #Sporangium #Paleontology #Branching (polymer chemistry) #Botany #Spore

paper · doi:10.1017/s026359330001018x

openalex publication_date 1983/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

ABSTRACT Recent collections of Sawdonia ornata have been made from the Strathmore Group which crops out in the Midland Valley of Scotland. The sediments are Lower Devonian, probably Emsian, in age. New morphological features discovered include planar branching of vegetative and fertile axes, abaxial emergences close to branch points and H branching. Well preserved cuticles have permitted reinterpretation of the structure of stornata, rosettes (hair bases), papillae and spines, and striated cuticle is identified as S. ornata . The morphology of sporangia and in situ spores is described. Pyritised axes have revealed details of xylem shape, maturation, changes in the vicinity of branching, tracheidal structure and the arrangement of xylem and cortex in deformed axes.

Citations

• A new species of Psilophyton from the Lower Devonian of northern New Brunswick, Canada
• The Occurrence, Structure and Functions of the Stomata in British Bryophytes
• THE SYSTEMATIC POSITION OF HICKLINGIA EDWARDII KIDSTON AND LANG
• XXIV.—On Old Red Sandstone Plants showing Structure, from the Rhynie Chert Bed, Aberdeenshire. Part I. Rhynia Gwynne-Vaughani, Kidston and Lang
• RECLASSIFICATION OF PSILOPHYTA
• XXVI.—On Old Red Sandstone Plants showing Structure, from the Rhynie Chert Bed, Aberdeenshire. Part III. Asteroxylon Mackiei, Kidston and Lang
• XXIV.—On Old Red Sandstone Plants showing Structure, from the Rhynie Chert Bed, Aberdeenshire. Part II. Additional Notes on Rhynia Gwynne-Vaughani, Kidston and Lang; with Descriptions of Rhynia major, n.sp., and Hornea Lignieri, n.g., n.sp.

Cited by

• Sawdoniales [wikipedia]