Up Primary xylem Oak wood Leaf vein Vein ends Bean seed Pine tracheids, xs Fern TE, xs Fern, TE, mag Annular walls Annular, stretched Annular, narrow Scalariform walls Scalar., narrow CBP, pine CBP, dicot CBP, irregular Contact faces Pits, side view CBP, pine, xs CBP,angio, xs CBP, fern, xs Contact face, xs Simple perf. plate 1 Simple perf. plate 2 Pitted perf. plate Perf. plate & helix Perf. plate, face Perf. plate, mag Perf. plate, section Perf. plate rim Perf. plate & wall Scalariform Per plate Primary xylem Vessel sizes Fern TE Pine needle VE precursor, ls Protoxylem 9 Contact faces VE precursor, xs Precursor 2 Torn vessel Torn vessel 2
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Fig.
7.2-5. Longitudinal section of club moss (Lycopodium).
Fig. 7.2-3 shows that club moss has narrow tracheary elements with annular
secondary walls; it also has narrow tracheids with scalariform pitting. Because
the tracheids are so narrow, the scalariform pit apertures cannot be really
wide, so these do not have the striking ladder-like appearance of the wide
tracheids in Fig. 7.2-4.
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