. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. 56 ORGANOGRAPnr. » stigmas are generally large, often furnished with hairs or dissected into plumes (Fig. 131) for the retention of the grains that may come in contact with them. The anthers are often suspended on capillary filaments, so as to be more directly exposed to the action of the wind. 72. When pollination is effected by insects, the flowers are said to be entomophilous (Gr. eniomon, insect; philos, lo
. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. 56 ORGANOGRAPnr. » stigmas are generally large, often furnished with hairs or dissected into plumes (Fig. 131) for the retention of the grains that may come in contact with them. The anthers are often suspended on capillary filaments, so as to be more directly exposed to the action of the wind. 72. When pollination is effected by insects, the flowers are said to be entomophilous (Gr. eniomon, insect; philos, loving). In these the amount of pollen produced is not so great, there being but little waste as compared with the loss when transported by the wind. It is not so dry and incoherent as in the anemophilous flowers; the grains are generally moist or slightly viscid, often provided with projections or entangling threads. In the Orchids and Milkweeds the pollen is in masses, supplied with viscid pedi- cels (Fig. 148). All these contrivances tend to insure the adherence of the pollen grains or masses to the head, legs, or body of the insects which visit the flowers, and thus efiect the transportation of the pollen to the stigmas of other flowers. Such flowers are further characterized by the possession of a large, showy perianth, or of odor, or by the secretion of nectar; or they may furnish all these attractions combined. 73. Of the special adaptations in hermaphrodite flowers, to insure cross-fertilization, dichogamy (Gr. diehoa, asun- der; gamos, union) is an important one; it means that the stamens and pistil of the same flower do not come to matu- rity at the same time, hence self-fertilization is impossible. The flower is proterandrous (Gr. protos, first; andres, stamens) when the anther ripens and discharges the pollen Fig. 131. Plumose stigma of a grass-flower {_roa ^rt^fensis).. Please note that these images are extracted from scanned page images that may have been digitally
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1883
