. Practical botany. Botany. THE STEM AND THE LEAF 47 One-year-old stems of dicotyledonous plants wliich are not climbers usually differ in structure from the type; showji in Fig. 29 mainly in having the l)undles more or less completely joined into a continuous cylinder (shown in the cross section as a ring, Fig. 30). 45. Strengthening cells. There are several kinds of cells wliicli give either touglmess, stiffness (Sect. 4(1), or both of these qualities to the parts of the plant body where they (iccur. Only four of these kinds need be mentioned m this place. The two shown in Fig. 82 are connii
. Practical botany. Botany. THE STEM AND THE LEAF 47 One-year-old stems of dicotyledonous plants wliich are not climbers usually differ in structure from the type; showji in Fig. 29 mainly in having the l)undles more or less completely joined into a continuous cylinder (shown in the cross section as a ring, Fig. 30). 45. Strengthening cells. There are several kinds of cells wliicli give either touglmess, stiffness (Sect. 4(1), or both of these qualities to the parts of the plant body where they (iccur. Only four of these kinds need be mentioned m this place. The two shown in Fig. 82 are conniionly found in the cortex of dicotyledons. CoUencliytna relia (J) are like the thin-walled cells of the pitli, but are reenforced at the angles, just as some packing â boxes have strips of board nailed fast on the inside of the-box at the junc- tions of the sides. Bast fibers (5) are extremely slender tubes, with closed and pointed ends, much like a jaiece of thermometer tubing drawn to a [loint in a gas flame and thus closed. Collenchyma gives moderate stiff- ness to the parts in which it occurs, and is highly elastic, so that it does not hinder the growth of the stem which it incloses. Bast fibers are flexible but very tough, and therefore enable the parts of the root, stem, or leaf in which they occur to resist being pulled 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 Bergen, Joseph Y. (Joseph Young), 1851-1917; Caldwell, Otis William, 1869- joint author. Boston, New York [etc. ] Ginn and company
Size: 1427px × 1750px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublisher, booksubjectbotany
