Fig. 3 in A new vesselless angiosperm stem with a cambial variant from the Upper Cretaceous of Antarctica

Fig. 3. SEM images of the secondary xylem of the chloranthacean angiosperm Sarcandraxylon sanjosense gen. et sp. nov. (IAA-Pb 621), San José Pass, Antarctica, early–middle Campanian. A. Transverse section of the stem, showing one vascular bundle in the middle, pith toward the right, white arrows pointing uniseriate fascicular rays. B. Parenchymatic cells of an interfascicular ray in transverse section showing the main shape and piritization of the cell walls. C. Secondary xylem in longitudinal tangential section, showing fascicular xylem (fx) and interfascicular rays (ir). D. Longitudinal section of fascicular xylem; D1, showing tracheids and a two cells tall uniseriate ray (white arrow) with elongate upright cells; D2, detail showing cell walls partially replaced with framboidal pyrite (white arrow). Scale bars: A, D, 100 μm; B, 40 μm; C, 200 μm; E, 50 μm.图3 采自南极洲圣何塞山口、白垩纪坎潘期早-中期的金粟兰科被子植物新属新种圣何塞草珊瑚木（Sarcandraxylon sanjosense gen. et sp. nov.，标本编号IAA-Pb 621）的次生木质部扫描电子显微镜（Scanning Electron Microscope, SEM）图像。A. 茎横切面，示中部1个维管束，髓位于右侧，白色箭头指示单列束状射线；B. 束间射线的薄壁细胞横切面，示细胞的主要形态及细胞壁的黄铁矿化特征；C. 次生木质部切向纵切面，示束状木质部（fx）与束间射线（ir）；D. 束状木质部纵切面；D1示管胞与由2个细胞构成的单列射线（白色箭头），射线细胞呈伸长直立状；D2为局部细节，示细胞壁部分被莓状黄铁矿交代（白色箭头）。比例尺：A、D为100 μm；B为40 μm；C为200 μm；E为50 μm。