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.
7.1-7b.
Magnification of vessel elements in fern (Pteridium). The three large
cells at the bottom of the micrograph are vessel elements. The two arrows
indicate the contact faces (it is possible to see that the “wall” between
two cells is actually two walls and a middle lamella). Although this looks like
an ordinary wall that you might see between two fibers, the paleness in each
indicates that there is a scalariform opening there. The opening happens to be a
perforation in this Pteridium, not a pit.
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