. Fossil plants : for students of botany and geology . Paleobotany. 376 BENNETTITALES [CH. has more compact wood than that of recent Gycads; the medullary rays are 1—2 cells broad except near the perimeduUary region where they are broader and the individual cells are tangentially stretched (fig. 508, B). The tracheids are scalariform, but in C. micromyela, an exceptional type, some of the xylem-elements have 1—2 rows of separate bordered pits (fig. 538). The phloem s. s Fig. 509. Cycadsoidea Wielandi. Tangential section of secondary xylem of the stem. (After Wieland; x 100.) (fig. 518, B)
. Fossil plants : for students of botany and geology . Paleobotany. 376 BENNETTITALES [CH. has more compact wood than that of recent Gycads; the medullary rays are 1—2 cells broad except near the perimeduUary region where they are broader and the individual cells are tangentially stretched (fig. 508, B). The tracheids are scalariform, but in C. micromyela, an exceptional type, some of the xylem-elements have 1—2 rows of separate bordered pits (fig. 538). The phloem s. s Fig. 509. Cycadsoidea Wielandi. Tangential section of secondary xylem of the stem. (After Wieland; x 100.) (fig. 518, B) is characterised by'an alternation of thick-walled elements and thiimer cells^. From the main stele branches are given ofi to supply the flowering shoots in the form of a cyhndrical stele Uke that of the primary axis, and each leaf-trace arises as a single bundle which, in the form of a U-shaped strand (fig. 519, A), 1 Wieland (06) p. 76; Capellini and Solms-Laubaoh (92) PI. v. fig. 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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