The most complete account of Grand’Eury’s views in regard to the anchoring and absorbing organs of _Sigillaria_ is given in his monograph on the Coal-field of Gard[590], St Étienne, and these are clearly stated also by Solms-Laubach[591] who confirms the conclusions of the French author as to the manner of development of the aerial shoots. Grand’Eury believes that both _Stigmaria_ and _Stigmariopsis_ are rhizomes and not true roots. The surface-features of _Stigmaria_ have already been described. This type Grand’Eury speaks of as characterised by the uniform diameter and considerable horizontal elongation of the bifurcated axes; he thinks they grew both as floating rhizomes and on the ground: they may frequently be traced for a considerable distance without showing any signs of connexion with aerial shoots, but occasionally they have been seen in organic union with Sigillarian stems. He believes that these rhizomes were produced as the result of germination under water of the spores of _Sigillaria_ or _Lepidodendron_ and developed as long and branched aquatic rhizomes capable of independent existence. Under certain conditions, as he thinks in shallower water, the rhizomes produced bulb-like outgrowths which grew into erect stems having the surface-features of _Sigillaria_. This method of origin is practically the same as that described by Goeppert in 1865. The vascular medullated cylinder of these erect branches was in direct continuity with that of the Stigmarian rhizomes. [Illustration: FIG. 207. An early stage in the development of _Sigillaria_. A. Surface-features enlarged. (After Grand’Eury.)] [Illustration: FIG. 208. Later stage in the development of _Sigillaria_; _Syringodendron_ with _Stigmariopsis_. (After Grand’Eury.)]