FIG. 15 in Bark anatomy of lianescent Bignoniaceae: a generic synopsis

FIG. 15. — Secondary phloem of Amphilophium: A-G, Amphilophium crucigerum; A-E, transverse sections; A, periderm with a stratified phellem, with an alternation of thick-walled lignified cells, and thin-walled, non-lignified cells. Phelloderm thick; B, prismatic crystals abundant in the phellem (arrowheads); C, included phloem wedge forms interxylary phloem in the genus. The cambium remains active and produce phloem in the enclosed wedgde, causing a conspicuous collapse of the nonconducting phloem; D, regular phloem with thin to thick fiber bands. A large portion of the nonconducting undergoes extensive collapse. Some of the rays greatly dilate by division of the ray margins, forming wedge shaped rays. Some ray cells undergo belated sclerosis forming sclereids (arrows); E, detail of the secondary phloem, showing turgid sieve tubes (arrows) with one companion cell lying on its corner. Loss of conductivity happens a few layers away from the cambium, with collapse of the sieve tubes (arrowheads); F, longitudinal radial section. Wide sieve tubes with simple sieve plates. Crystalliferous parenchyma bearing prismatic crystals around fiber band; G, longitudinal tangential section, regular phloem. Axial parenchyma storied, rays wide, with over 5 cells in width. Abbreviations: cz, cambial zone. Scale bars: A, C, G, 200 μm; B, F, 100 μm; D, 600 μm; E, 50 μm.