Schizoneura gondwanensis Feist. Fig. 69, A and B.
This species is represented by numerous specimens from the Lower Gondwana rocks of India[576]; it is characterised by narrow articulated stems which bear large leaf-sheaths at the nodes. The sheaths may have the form of two large and spreading elongate-oval lobes, each of which is traversed by several veins (fig. 69, B), or the lobes may be further dissected into long linear single-veined segments, as in fig. 69, A. It is supposed that in the young condition each node bears a leaf-sheath consisting of laterally coherent segments which, as development proceeds, split into two or more lobes. Feistmantel records this species from the Talchir, Damuda and Panchet divisions of the Lower Gondwana series of India; these divisions are regarded as equivalent to the Permo-Carboniferous and Triassic rocks of Europe. The two specimens shown in fig. 69 are from the Lower Gondwana rocks of the Raniganj Coal-field, India.
As already pointed out[577], some of the specimens of flat and broader stems referred by Feistmantel to Schizoneura are identical in appearance with stems which have been described from India and elsewhere as species of Phyllotheca.
Fig. 69. Schizoneura gondwanensis Feist. (After Feistmantel; slightly reduced.)
There are a few specimens of S. gondwanensis in the British Museum, but the genus is poorly represented in European collections.
A similar plant was described in 1844 by Schimper and Mougeot[578] from the Bunter rocks of the Vosges as Schizoneura paradoxa. This species bears a very close resemblance to the Indian forms, and indeed it is difficult to point to any distinction of taxonomic importance. Feistmantel considers that the European plant has rather fewer segments in the leaf-sheaths, and that the Indian plant had somewhat stronger stems. Both of these differences are such as might easily be found on branches of the same species. It is, however, interesting to notice the very close resemblance between the Lower Trias European plant and the somewhat older member of the Glossopteris flora recorded from India and other regions, which probably once formed part of that Southern Hemisphere Continent which is known as Gondwana Land[579].
CHAPTER X.
I. EQUISETALES (continued).