. The essentials of botany. Botany. 240 BOTANY. they soon become connected by a cambium-ring as in the Gymnosperms. In the perennial species this gives rise to a marked difference in the structure of the stem (Fig. 135, A and B). 509. The tissues of Angiosperms are the most varied and highly developed of any in the vegetable kingdom. Not only is every tissue abundantly represented, but each one shows almost numberless more or less well-marked va-. Fio. 135.—Cross-sections of tree-trunks. A, of a Palm; B, of an Oak; Ig, woody, and 6c, cortical (bark), portion; m, pith; rm, medullary rays. rieti
. The essentials of botany. Botany. 240 BOTANY. they soon become connected by a cambium-ring as in the Gymnosperms. In the perennial species this gives rise to a marked difference in the structure of the stem (Fig. 135, A and B). 509. The tissues of Angiosperms are the most varied and highly developed of any in the vegetable kingdom. Not only is every tissue abundantly represented, but each one shows almost numberless more or less well-marked va-. Fio. 135.—Cross-sections of tree-trunks. A, of a Palm; B, of an Oak; Ig, woody, and 6c, cortical (bark), portion; m, pith; rm, medullary rays. rieties. Moreover,; the structures which they form, as the solid (woody) parts of the stems, are of a higher order and far more complex than those in any other groups of plants. Practical Studies.—(a) Make cross-sections of young stems of the asparagus and hickory. Note tlie difference in arrangement of the bundles. In lilie manner compare cross-sections of young stems of virgin's-bower (Clematis) and green-brier (Smilax). (b) Make vertical sections of the foregoing, and note the relation of the bundles to tlie leaves. (c) Make cross and longitudinal sections of the solid (woody) part of a bamboo or green-brier stem, and compare with similar sections of oak or hickory. In the latter note the pith, medullary rays, and distinct bark, not present in the former. (d) In the sections of oak and hickory note the cambium-zone. 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 Bessey, Charles E. (Charles Edwin), 1845-1915. New York, Holt
Size: 2207px × 1132px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1884
