. Plant studies; an elementary botany. Botany. Fig. 123 A fruit of witch hazel discharging its seeds.—After Beal. light or sandy soil (see Fig. 120). When the work of the season is over, and the absorbing rootlets have shriveled, the plant is easily broken from its roots by a gust of wind, and is trundled along the surface like a light wicker ball, the ripe seed ves- sels dropping their seeds by the way. In case of an obstruction, such as a fence, great masses of these tumble- weeds may often be seen lodged against the windward side. 79. Discharge of spores.—In many plants the distribution of
. Plant studies; an elementary botany. Botany. Fig. 123 A fruit of witch hazel discharging its seeds.—After Beal. light or sandy soil (see Fig. 120). When the work of the season is over, and the absorbing rootlets have shriveled, the plant is easily broken from its roots by a gust of wind, and is trundled along the surface like a light wicker ball, the ripe seed ves- sels dropping their seeds by the way. In case of an obstruction, such as a fence, great masses of these tumble- weeds may often be seen lodged against the windward side. 79. Discharge of spores.—In many plants the distribution of spores and seeds is not provided for by any of the methods just mentioned, but the vessels containing them are so constructed that they are discharged with more or less violence and are some- what scattered. Many spore cases, especially those of the lower plants, burst irregularly, and with sufficient violence to throw out spores. In the liverworts pecu- liar cells, called elaters or "jumpers," are formed among the spores, and when the wall of the spore case is ruptured the elaters are liberated, and by their active motion assist in discharging the spores. In most of the true mosses the spore case opens by pushing off a lid at the apex, which exposes a delicate fringe of teeth covering the mouth of the urn-like case. These teeth bend in and out of the open spore case as they become moist or. Fig. 123. A pod of wild bean bursting, the two valves violently twisting and dis- charging the seeds.—After 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 Coulter, John Merle, 1851-1928. New York, D. Appleton and Company
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