. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. BBTOPSTTA. 151. 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 gr
. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. BBTOPSTTA. 151. 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).. 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
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1883
