. Fundamentals of botany. Botany. LIFE HISTORY OF A FERN 165 very small percentage of them would be able to develop into new plants. When the spores are ripe, the spore-case opens, and by various movements the spores are expelled. That sporangia are able to throw the spores to a considerable distance may be shown in a very simple way by placing a portion of a sporophyll with mature sporangia on a sheet of white paper, with the fruit-dots uppermost, and covering it with a large beU-jar. Within a few hours the scattered spores may be seen against the white background of the paper, and the greate
. Fundamentals of botany. Botany. LIFE HISTORY OF A FERN 165 very small percentage of them would be able to develop into new plants. When the spores are ripe, the spore-case opens, and by various movements the spores are expelled. That sporangia are able to throw the spores to a considerable distance may be shown in a very simple way by placing a portion of a sporophyll with mature sporangia on a sheet of white paper, with the fruit-dots uppermost, and covering it with a large beU-jar. Within a few hours the scattered spores may be seen against the white background of the paper, and the greatest dis- tance to which they have been thrown may be easily measured (Fig. 124).. Fig. 125.—Germination of the spores of a fern, a, Before germination; b, early stage, showing protonema (.pr.), and first rhizoid (rh); c, d, e, f, successive stages in the development of the prothallus. 151. Germination of Spores.—After dispersal, and under favoring conditions of temperature, moisture and light, the spore begins to absorb water, and soon com- mences to grow. As the internal osmotic pressure in- creases, the walls of the spore are burst apart, and a tiny. 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 Gager, C. Stuart (Charles Stuart), 1872-1943. Philadelphia, P. Blakiston's son & co.
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Keywords: ., bookauthorgag, bookcentury1900, bookdecade1910, booksubjectbotany
