. Fossil plants : for students of botany and geology . Paleobotany. XVIl] STIGMAEIOPSIS 237 tap-roots. Grand'Eury's conclusions are briefly as follows : Sigillaria, and we may add Lepidodendron, had no true roots and in this respect are comparable with Psilotum (fig. 118): the organs which are described by Grand'Eury as roots are correctly so named in a physiological sense, but morphologically they do not strictly conform, either in origin or in the arrange- ment of their appendages, to true roots. The question as to whether they are entitled to the designation root is one which it is needless
. Fossil plants : for students of botany and geology . Paleobotany. XVIl] STIGMAEIOPSIS 237 tap-roots. Grand'Eury's conclusions are briefly as follows : Sigillaria, and we may add Lepidodendron, had no true roots and in this respect are comparable with Psilotum (fig. 118): the organs which are described by Grand'Eury as roots are correctly so named in a physiological sense, but morphologically they do not strictly conform, either in origin or in the arrange- ment of their appendages, to true roots. The question as to whether they are entitled to the designation root is one which it is needless and indeed futile to discuss in detail; it would be conceding too much to a formal academic standpoint to refrain from applying to them the term root, as that best describes their share in the life of the Sigillarian stems. The horizontal Stigmarian axes are rhizomes in the ordinary sense of the term and from these were developed Sigillarian shoots, characterised. Fio. 209. Stigmariopsis and "; (After Grand'Eury.) in the lower portions by large parichnos strands. From the base of the young bulbous shoots roots were formed: these roots being, in the French specimens, of the Stigmariojjsis type. These conclusions require some modification when applied to British representatives of the arborescent Lycopodiales. The long spreading and dichotomously branched root-like organs attached to the base of Sigillarian and Lepidodendron stems are true examples of Stigmaria ficoides or other species. Stig- mariopsis occurs but rarely. This marked difference between French and English specimens may be explained if we adopt the opinion of Solms-Laubach, who believes that the true Stigmaria represents both the parent rhizome and the later- formed roots of the Rhytidolepis Sigillarian species and of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may
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