. Botany of the living plant. Botany. 236 BOTANY OF THE LIVING PLANT by a non-functional staminode (Fig. 183), while in others of the family it may be absent. In Veronica the two anterior stamens are also abortive. The two posterior petals fuse so that the corolla appears to be four-lobed ; the posterior sepal, which is present in the Mullein, is represented in some species of Veronica by a sepal smaller than the rest ; in other species it is absent, as in Veronica chamaedrys and the most of the Rhinantheae. Thus the flower, though typically pentamerous, has by stages of meiomery. Fig. 184. Di
. Botany of the living plant. Botany. 236 BOTANY OF THE LIVING PLANT by a non-functional staminode (Fig. 183), while in others of the family it may be absent. In Veronica the two anterior stamens are also abortive. The two posterior petals fuse so that the corolla appears to be four-lobed ; the posterior sepal, which is present in the Mullein, is represented in some species of Veronica by a sepal smaller than the rest ; in other species it is absent, as in Veronica chamaedrys and the most of the Rhinantheae. Thus the flower, though typically pentamerous, has by stages of meiomery. Fig. 184. Dissections of flowers of Lychnis dioica. I., II., VIII., the pistillate flower in which the stamens are represented only by staminodes [st). III., IV., IX., the pistillate flowers in which the gynoecium is represented only by a vestigium {gyn). i become apparently tetramerous. Similar changes occur in the Plantains and Teasels. Such examples serve to show that meiomer}^ by abortion may affect any of the series of parts, and not unfrequently more than one of them in the same flower. It is probably the cause of greater divergence of detail in flowers than any other factor. The most important cases are, however, those where one or other of the essential organs may be wholly abortive. It frequently occurs that flowers typically hermaphrodite may be staminate or pistillate, by 1. 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 Bower, F. O. (Frederick Orpen), 1855-1948. London, Macmillan
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1919
