. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. THE FLO WEB. 57 before the stigma reaches maturity. If the stigma is in a receptive condition before the pollen escapes, the flower is proterogynous (Gr. guna, pistil). Among the anemo- philous flowers the common Plantain furnishes an example of Proterogyny. The long, slender, hairy stigmas may be seen protruding from the unopened perianth while the anthers are yet enclosed. Only pollen from other flowers, ther
. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. THE FLO WEB. 57 before the stigma reaches maturity. If the stigma is in a receptive condition before the pollen escapes, the flower is proterogynous (Gr. guna, pistil). Among the anemo- philous flowers the common Plantain furnishes an example of Proterogyny. The long, slender, hairy stigmas may be seen protruding from the unopened perianth while the anthers are yet enclosed. Only pollen from other flowers, therefore, can effect the fertilization. Later the stigmas •wither, and the corolla expands; the four anthers now appear supported on long, delicate filaments, and their pollen is carried to stigmas of other Plantain-flowers which may have a synchronous maturity. 74. A Proterogynous example among entomophilous flowers is fur- nished by the Scrophularia. The flow- ers are visited by bees for the nectar, which is secreted by glands at the bottom of the corolla. The lower lobe of the irregular corolla serves as a landing-place for the bees. The mature pistil projects, as seen in Fig. 132, when the flower first opens; and fertilization now takes place,the pollen coming from another flower of the same sort. The position of the unripe stamens at this time is not seen in the figure, for the filaments are curved and the unripe anthers are deep down in the corolla. A day or two later the anthers, now ma- ture, appear at the mouth of the corolla, as is shown in Fig. 133. By this time the stigma, previously fertilized, is no longer in a receptive condition, and lies half-withered on the lower petal. Bees, visiting the flower, would come in contact with the anthers, and the pollen grains that adhered Figs. 132,133, Proterogynous flowers of Scrophularia nodosa : 132. First stage; Stigma mature; 133. Second stage; Anthers mature; p, pistil; an, Please note that these images are extra
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1883
