. Plants; a text-book of botany. Botany. SHOOTS. 69 This has the general result of placing the leaf blades at right angles to the rays of light, and in this respect the heliotropism of the stem aids in securing a favorable leaf position (see Figs. 63, 63a). Prostrate stems are differently affected by the light, however, being directed transversely to the rays of light. The same is true of many foliage. Fig. 60. An oak in its winter condition, showing ttie wide branching. The various directions of the branches have been determined by the light-relations. branches, as may be seen by observing al
. Plants; a text-book of botany. Botany. SHOOTS. 69 This has the general result of placing the leaf blades at right angles to the rays of light, and in this respect the heliotropism of the stem aids in securing a favorable leaf position (see Figs. 63, 63a). Prostrate stems are differently affected by the light, however, being directed transversely to the rays of light. The same is true of many foliage. Fig. 60. An oak in its winter condition, showing ttie wide branching. The various directions of the branches have been determined by the light-relations. branches, as may be seen by observing almost any tree in which the lower branches are in the general transverse posi- tion. These branches generally tend to turn upwards when they are beyond the region of shading. Subterranean stems are also mostly horizontal, but they are out of the influence of light, and under the influence of gravity, known as geotropism, which guides them into the trans- verse position. The climbing stem, like the erect one,. 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 Coulter, John Merle, 1851-1928. New York, D. Appleton and company
Size: 1737px × 1439px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1900
