. Botany for high schools and colleges. Botany. 356 BOTANY. exospore, which is generally yellow in color. Internally the spores contain, in addition to the protoplasm, oil-drops and chlorophyll granules. 465.—In the germination of the spores, the exospore is ruptured, and the endospore protrudes as a tubular filament, which elongates by the continued growth of an apical cell; partitions form at close intervals, and the threads branch freely, giving rise to a green Conferva-like mass, the pro- tonema (Fig. 245, B). In the Sphngnacem, however, the protonema is a flattened mass, somewhat like the
. Botany for high schools and colleges. Botany. 356 BOTANY. exospore, which is generally yellow in color. Internally the spores contain, in addition to the protoplasm, oil-drops and chlorophyll granules. 465.—In the germination of the spores, the exospore is ruptured, and the endospore protrudes as a tubular filament, which elongates by the continued growth of an apical cell; partitions form at close intervals, and the threads branch freely, giving rise to a green Conferva-like mass, the pro- tonema (Fig. 245, B). In the Sphngnacem, however, the protonema is a flattened mass, somewhat like the plant-body. We. 245.—Development of Fimaria hygrometrica. A, germinating spores ; «, rnp- turoa exospore ; w, w, young root liaire—on ttie oppopite s'de of the spore is the beginning of the protonema ; r, vacm^le in a germinating spore. B, part of a proto- nema three weelts after germinati(m ; A, a primary shoot with lirown walls—from it arise several lateral branches b. K, a young bud or rudiment of a leaf-bearing axis ; w, a small root liair. .1 X 650 ; .8 X 70.—After Sachs. of the lower Liverworts. After a greater or less period of vegetation, there arise upon the protonema small buds, which develop into leaf-bearing axes (Fig. 245, B, K). These buds originate from single cells, which repeatedly divide them- selves by diagonal partitions; the apical cell thus formed in each case becomes the apical cell of the bud, and the new axis. The leafy axes thus formed sooner or later bear the sexual organs, thus completing the round of life. 466.—Mosses reproduce themselves asexually, sometimes in a manner quite similar to that of the Liverworts—, in. 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 Bessey, Charles E. (Charles Edwin), 1845-1915. New York : H. Holt
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1885
