. Botany of the southern states. In two parts. Botany. THE STEM. 33 the regular deposition of wood, and would interfere more or less with the regular formation of bark, especially toward the top of the stem. This is the case with monocotyledonous arbo- rescent stems. 61. If we make a longitudinal section of a stem of the dwarf Palmetto, we shall observe the following appearances. We find it composed of numerous fibers, interlacing in all directions ; but the general direction of the threads, if we commence at the top, is toward the center, where they curve toward the circumference, Fis- 2?- 1
. Botany of the southern states. In two parts. Botany. THE STEM. 33 the regular deposition of wood, and would interfere more or less with the regular formation of bark, especially toward the top of the stem. This is the case with monocotyledonous arbo- rescent stems. 61. If we make a longitudinal section of a stem of the dwarf Palmetto, we shall observe the following appearances. We find it composed of numerous fibers, interlacing in all directions ; but the general direction of the threads, if we commence at the top, is toward the center, where they curve toward the circumference, Fis- 2?- 1 Fig. 25. Fig. A transverse section of a portion of the Yucca .erloriosa, from the center to the cir- cumference. Transverse section of a fibro- vascular bundle of a mono- cutyledonous stem. Longitudinal section of a mo- nocotyledonous stem. Fig. 27. The point where the bundle approaches nearest the center is where the base of the leaf has its origin, and sends out bundles toward the circumference. The curve from that point to the base of the leaf is the track that the base of the leaf has taken in its growth. These bundles are composed of woody fiber, tubes, and spiral vessels (Fig. 26), toward the top, or nearest the leaf, and of tubes and woody fiber toward the bottom, and ending in woody fiber only. 62• All the leaves have their origin at the center of the stem at the top, around the base of a central vesicle. As new leaves are formed and raised up, the older ones are pushed out by the deposition of cellular matter, and come to the lateral surface of the stem, and then all the new matter goes down on the out- side, like a dicotyledon, and forms wood and bark. 63. All monocotyledons are constructed on the same general principle, and most of the variations are explicable by the greater 61. What is the appearance of a longitudinal section of the dwarf pal- metto ? What is the point where the bundles approach nearest the center? What is the curve from that point to the ba
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Keywords: ., bookcentury1800, bookdecade1860, booksubjectbotany, bookyear1866
