III. The Genus <i>Gephyrostegus</i>

Abstract

Abstract Gephyrostegus bohemicus Jaekel from the Upper Carboniferous of Nyran is the oldest and most primitive member of the Seymouriamorpha. A new description is given based partly on the described material, but mainly on two hitherto undescribed specimens. These specimens are remarkably complete and make possible a description of the palate, previously unknown, and also a comparative study of the development of the vertebrae.