. Botany for high schools and colleges. Botany. 104 BOTANY. {h) Water-pores. De Bary* describes under this name some curious stoma-like structures which occur on many plants. These, instead of containing air in their cavities, normally contain water. Their guard- cells, which are, in some cases at least, much like those of ordinary stomata, are immovable, and as a consequence the pore is incapable of enlargement or contraction. They are always found over the ends of small bundles of spiral vessels, which appear to pass into the pore cav- ities. One form of these may be readily examined in the
. Botany for high schools and colleges. Botany. 104 BOTANY. {h) Water-pores. De Bary* describes under this name some curious stoma-like structures which occur on many plants. These, instead of containing air in their cavities, normally contain water. Their guard- cells, which are, in some cases at least, much like those of ordinary stomata, are immovable, and as a consequence the pore is incapable of enlargement or contraction. They are always found over the ends of small bundles of spiral vessels, which appear to pass into the pore cav- ities. One form of these may be readily examined in the leaves of the fuch-. Fig. 93. Fig. 94. Fig. 93.—Surface view of the water-pore on the extremity of the leaf-tooth of Fuch- sia globosa. X 500.—After Arthur. Fig. 94.—Transverse section of leaf-tooth of Fuchsia globosa; cp, chlorophjil- bearmg parenchyma, within which is the fibro-vascular bundle; ra, raphis-cells. X 125.—After Arthur. sia, and the primrose {Primula sinensis). In the fuchsia they are found in the papillae or small teeth on the margins of the leaves, and in ihe primrose, in the papillae terminating the lobes and lobules. In Fuchda globosa each leaf-tooth is provided with a single terminal pore (in some of the dark colored varieties there are several), which resembles an ordinary stoma (Fig. 93). Beneath the pore is a cavity, commonly filled with water (Fig. 95, &), which, by evaporation, deposits calcium car- bonate upon the walls of the lining cells, thereby discoloring them. A fibro-vascular bundle is continued from the veins of the leaf through * In '* Vergleichende Anatomie der Vegetationsorgane," etc., 1877, on page 54, et sea. References are there given to the literature of the subject, which is both recent and limited. After Mettenius' paper in Filices Jiorti Lipsiensis, others appeared by other writers in Botanische ZeUung, 1869, 1870, and Please note that these images are extracted from scanned page images that may have been digit
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