. Fossil plants : for students of botany and geology . Paleobotany. XLV] ELATIDES 273 absence of cones the latter species is retained in Pagiophyllum. From the Wealden species E. curvifolia, E. Williamsonis differs in its stouter and more crowded leaves though the differences are slight both in the cones and vegetative shoots. In all probability this species is represented in several Jurassic floras, but unless cones are present specimens should be referred to Pagiophyllum. Elatides curvifolia (Dunker). Dunker^ first described this Wealden type (fig. 743) from North Germany as Lycopodites and
. Fossil plants : for students of botany and geology . Paleobotany. XLV] ELATIDES 273 absence of cones the latter species is retained in Pagiophyllum. From the Wealden species E. curvifolia, E. Williamsonis differs in its stouter and more crowded leaves though the differences are slight both in the cones and vegetative shoots. In all probability this species is represented in several Jurassic floras, but unless cones are present specimens should be referred to Pagiophyllum. Elatides curvifolia (Dunker). Dunker^ first described this Wealden type (fig. 743) from North Germany as Lycopodites and it was referred by Ettingshausen^ to Araucarites, the generic name, though probably correctly express-. FiG. 743. Elatides curvifolia. (After Nathorst; nat. size.) ing the position of the fossil Conifer, being used without adequate reasons. The identity of the cones discovered by Nathorst* in the Wealden or Upper Jurassic beds of Spitzbergen with those on which Heer founded the genus Elatides led to the adoption of that generic term. Nathorst's discovery of several fertile branches justifies his reference of Heer's specimens from Spitzbergen described as Sequoia Reichenhachii^ to Elatides curvifolia, as also the employment of Dunker's specific term for Elatides ovalis and E. Brandtiana Heer. The cones of E. curvifolia are cylindrical or oval and it is suggested by Nathorst that these forms might be regarded as varieties, the oval form being spoken of as var. ovalis 1 Dunker (46) A. p. 20, PI. vn. fig. 9. 2 Ettingshausen (52) PL n. » Nathorst (97) pp. 35, 58, Pis. i., n., iv., vi. ' Heer (75) ii. PI. xxxvi. figs. 1—8; PI. xxxvii. figs. 1, 2. s. IV 18. 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 Seward, A. C. (Albert Charles), 1863-1941. Cambridge : University Press
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