. Studies in fossil botany . Paleobotany. 324 STUDIES IN FOSSIL BOTANY Corynepteris is at present only known from impres- sions ; we may compare with it a genus, Diplolabis, Renault,1 which has been studied entirely in petrified material. The stem is unknown, but the structure of the petiole indicates affinity with Zygopteris. In both the species described, D. forensis, from the Upper Coal- measures, and D. esnostensis, of Lower Carboniferous age, the fructifications are described as synangia, with. Fig. 120.—Asterochlaena laxa. Part of transverse section of stem with surrounding petioles. The
. Studies in fossil botany . Paleobotany. 324 STUDIES IN FOSSIL BOTANY Corynepteris is at present only known from impres- sions ; we may compare with it a genus, Diplolabis, Renault,1 which has been studied entirely in petrified material. The stem is unknown, but the structure of the petiole indicates affinity with Zygopteris. In both the species described, D. forensis, from the Upper Coal- measures, and D. esnostensis, of Lower Carboniferous age, the fructifications are described as synangia, with. Fig. 120.—Asterochlaena laxa. Part of transverse section of stem with surrounding petioles. The deeply lobed stele is shown, also the leaf-traces and the curved bundles in the petioles. Nat. size. After Stenzel. From Tansley. New Pliytologist. from three to six sporangia attached to a common central receptacle. The sporangia differ from those of Corynepteris in having no differentiated annulus. It is also probable that the synangia were borne on a naked rachis, and not on an expanded lamina, as in the former genus. Two genera, of which only the vegetative anatomy is known, may be shortly mentioned. Anachoropteris, 1 Flore fossile d'Autun et d'Epinac, t. ii. p. 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 not perfectly resemble the original Scott, Dukinfield Henry, 1854-1934. London, A. and C. Black
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