. Botany for secondary schools; a guide to the knowledge of the vegetation of the neighborhood. Plants. 136 FERTILIZATION AND POLLINATION proterogynous. (Aner, andr, is a Greek root often used, in combinations, for stamen, and gyne for pistil.) The dif- ference in time of ripening may be an hour or two, or it may be a day. The ripening of the stamens and pistils at different times is known as dichogamy, and flowers of such character are said to be dichog- amous. There is little chance for dichogamous flowers to pol- linate themselves. The holly- hock is proterandrous. Fig. 222 shows a flower r
. Botany for secondary schools; a guide to the knowledge of the vegetation of the neighborhood. Plants. 136 FERTILIZATION AND POLLINATION proterogynous. (Aner, andr, is a Greek root often used, in combinations, for stamen, and gyne for pistil.) The dif- ference in time of ripening may be an hour or two, or it may be a day. The ripening of the stamens and pistils at different times is known as dichogamy, and flowers of such character are said to be dichog- amous. There is little chance for dichogamous flowers to pol- linate themselves. The holly- hock is proterandrous. Fig. 222 shows a flower recently ex- panded. The center is occupied by the column of stamens. In Fig. 223, showing an older flower, the long styles are con- spicuous. Many flowers are im- perfectly k dichogamous—some of the anthers mature simul- taneously with the pistils, so that there is chance for self-pol- lination in case foreign pollen does not arrive. Even when the stigma receives pollen from its own flower, cross-fertilization may result. 281. Some flowers have so developed as to prohibit self- pollination. Very irregular flow- ers are usually of this cate- gory. Regular flowers usually depend on dichogamy and on the impotency of pollen on the pistil of the same flower. Flowers that are very irregular and provided with strong perfume are usually pollinated by insects. Gaudy colors probably attract insects in many cases, but odor appears to be a greater attraction. The insect visits the flower for the. 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 Bailey, L. H. (Liberty Hyde), 1858-1954. New York, Macmillan
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1913
