. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. of trees. Besides the sexual r'eproduction by means of archegonia and antheridia, they multiply extensively in a non-sexual manner; namely, by the production of peculiar buds, called gemma (Fig. 263, gem). These, in the common Liverwort {Marckantia), are little cellular bodies, developed in cups, ou the upper surface of the thallus. When the gemmae are full-grown, they fall to the ground, and grow directly into
. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. of trees. Besides the sexual r'eproduction by means of archegonia and antheridia, they multiply extensively in a non-sexual manner; namely, by the production of peculiar buds, called gemma (Fig. 263, gem). These, in the common Liverwort {Marckantia), are little cellular bodies, developed in cups, ou the upper surface of the thallus. When the gemmae are full-grown, they fall to the ground, and grow directly into new plants. The stomates in these plants are 2«3, not of the ordinary kind found in higher groups; instead of being surrounded, as there, by two guard-cells, there are sixteen (or more) cells, in four (or more) superposed layers, encircling the orifice, which leads into a large air-cavity below the epidermis. In this cavity are branching rows of cells, which contain the chlorophyll-masses (Fig. 264). 2. Musci. This group includes the Sphagnums and the true Mosses. The plants (Fig. 262) have stems, with sessile leaves and articu- lated root-hairs, or rhizoids; the leaves are composed of a single layer of cells, and may, or may not, have a midrib. The st^ms may have an outer, thickened layer, or layers (imperfect scle- renchyma); and within, either simply thin-walled parenchyma, or an axial bundle of very narrow, thin-walled cells—imperfect fibro-vascular Fig. 263. A portion of a Liverwort, with the gemmae in cup-Ukc cavities. Fig. 264. Section of a frond of Liverwort, showing the stomate (si) and the air-cavity (a) below, containing the cells which have the chlorophyll (cU).. 264. 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 Kellerman, William Ashbrook, 1850-1908. Philadelphia, J. E. Potter and Company
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1883
