XIII.—A new interpretation of Lepidodendron calamopsoides Long and Oxroadia gracilis Alvin

Abstract

Synopsis A petrified lycopod found in a loose block of calciferous sandstone from the Cementstone Group in Berwickshire possesses a rooting stem-base similar to others previously assigned to Lepidodendron calamopsoides (Long 1964) but it shows continuity with a dichotomously branched stem about 15 cm. long, lacking leaves, but otherwise resembling Oxroadia gracilis (Alvin 1965). The diagnosis of Lepidodendron calamopsoides has been emended to include only axes bearing lepidodendroid leaf cushions as previously described. The new specimen, and others with like roots are tentatively assigned to Oxroadia gracilis Alvin.