. The anatomy of woody plants. Botany -- Anatomy. 3 6o THE ANATOMY OF WOODY PLANTS largely into its composition, and these are often in the condition of septation. The ray, in fact, is a composite structure, organized only partially from true radial parenchyma and also consisting largely of transformed longitudinal fibrous elements of the wood. These first become septate, and, particularly in the more external regions of the wood, their divisions become progressively more and more like the ordinary storage elements of the ray. Fig. 258 por- trays the longitu- dinal organization of the wood in
. The anatomy of woody plants. Botany -- Anatomy. 3 6o THE ANATOMY OF WOODY PLANTS largely into its composition, and these are often in the condition of septation. The ray, in fact, is a composite structure, organized only partially from true radial parenchyma and also consisting largely of transformed longitudinal fibrous elements of the wood. These first become septate, and, particularly in the more external regions of the wood, their divisions become progressively more and more like the ordinary storage elements of the ray. Fig. 258 por- trays the longitu- dinal organization of the wood in the outer region of a rather thick stem of Ephedra calif or nica. The large rays are here conspicuous and numerous, but not of equal size. In general, those of greater dimensions have originated in the region of the medulla, while those less conspicu- ous by their size have come into ex- istence more re- cently. The small degree of magnification employed in the figure does not make it possible to discern clearly the composite character of the radial parenchyma. The next illustration, Fig. 129, which reproduces one of the smaller radial masses under a higher magnifica- tion, makes the organization of these structures apparent. Obvi- ously not only ordinary radial parenchyma is concerned in the constitution of the rays, but also numerous fibers and even vessels. It may here be stated, although that situation is not clearly shown in the illustration, that fibers are seen in such rays in all conditions of transformation into elements resembling the ordinary radial parenchyma. In the genus Ephedra we have the wedding, as. FIG. 258.—Tangential view of a large ray of Ephedra in its external 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 Jeffrey, Edward C. (Edward Charles), b. 1866. Chicago, Ill. , The U
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