. A textbook of botany for colleges and universities ... Botany. Fig. 766. — A cross section of a succulent leaf, that of Begonia, show- ing centrally placed chlorenchyma (c), consisting of funnel-shaped palisade cells (p) whose chloroplasts are grouped chiefly at the basal end, and loosely arranged sponge cells (/); note the heavy epidermis («), averaging three cells in thickness above and two be- neath, and quite without chloroplasts; such an epidermis represents a peripheral water tissue; considerably Fig. 767.—A cross section of the upper part of a succulent xerophytic leaf, th
. A textbook of botany for colleges and universities ... Botany. Fig. 766. — A cross section of a succulent leaf, that of Begonia, show- ing centrally placed chlorenchyma (c), consisting of funnel-shaped palisade cells (p) whose chloroplasts are grouped chiefly at the basal end, and loosely arranged sponge cells (/); note the heavy epidermis («), averaging three cells in thickness above and two be- neath, and quite without chloroplasts; such an epidermis represents a peripheral water tissue; considerably Fig. 767.—A cross section of the upper part of a succulent xerophytic leaf, that of the purslane {Porlulaca oleracea), showing a festoon (t) of funnel-shaped cells with large basal chloroplasts grouped about a small vein (v), and an outer ring of palisade cells (p), containing chloroplasts of ordinary size; note that the palisades are not symmetrically placed but appear to be oriented with respect to the incident light; the epidermis (e) is two cells thick and represents a peripheral water tissue; highly magnified. filaments, which contrast with the compact tissues elsewhere; in the leaf of Polytrichum similar filaments form vertical plates hanging loosely from the leaf body. Near the base of some moss capsules the chlorenchyma is differentiated into palisade and sponge tissue, much as in seed plants (fig. 263). In lichens the chlorenchyma consists of the algal layer, which lies close to the surface in shade forms and deeper in sun forms (fig. 1112). The influence of external factors upon the form and orientation of chlorench3mia cells. — The plasticity of chlorenchyma. — Chlorenchyma is one of the most plastic of plant tissues, its thickness, its compactness, and even its differentiation into pahsade and sponge often being subject. 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 wo
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1910
