. The anatomy of woody plants. Botany -- Anatomy. CONIFERALES 339 the relationship of Pinus to the other Coniferales. An excellent illustration of the value of anatomical evidence in the case of this problem is furnished by the interesting taxodineous genus Sequoia. The Taxodineae as well as the nearly allied Cupres- sineae are characterized anatomically by the organization of the female cone and the structure of the wood. The scales of the cone are superficially single, but in section they show the presence of a double series of oppositely orientated fibrovascular bundles, thus indicating the
. The anatomy of woody plants. Botany -- Anatomy. CONIFERALES 339 the relationship of Pinus to the other Coniferales. An excellent illustration of the value of anatomical evidence in the case of this problem is furnished by the interesting taxodineous genus Sequoia. The Taxodineae as well as the nearly allied Cupres- sineae are characterized anatomically by the organization of the female cone and the structure of the wood. The scales of the cone are superficially single, but in section they show the presence of a double series of oppositely orientated fibrovascular bundles, thus indicating the origin of the seed scales from the externally. FIG. 246.—Transverse section of the cone scale of Sequoia gigantea, showing a double system of bundles with opposite orientation. double structures of the ovuliferous cone of the Abietineae (Fig. 246). In the organization of their wood the Taxodineae differ from the Abietineae in the absence of resin canals. There is, how- ever, a resiniferous secretion produced by scattered parenchymatous elements of the wood. In the structure of the radial parenchyma a condition of simplicity contrasting with that found in the Abie- tineae is manifested, for the marginal tracheids of the rays of the Abietineae are conspicuously absent in the normal wood of the Taxodineae in general and of Sequoia in particular. If we con- sider the genus Sequoia in the light of the canons of anatomy formulated above, very interesting results are reached. First, if a transverse section of the axis of the cone or of the ovuliferous scale of Sequoia gigantea be examined, resin canals reveal them- selves in the wood in proximity to the primary xylem (Fig. 247).. 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 University of Chicag
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