. Nature and development of plants. Botany. 424 THE ORCHIDALES into a waxy mass, pollinium (pi. pollinia) which is attached to a sticky part of the rostellum (Fig. 293, B,C). The remarkable feature about these gaudy flowers is the relation that the label- lum, anther, rostellum and stigma sustain to each other. The position of these organs is such that an insect visiting the flower touches with some part of his body the sticky part of the rostel- lum and the pollinia are thus made fast to him and carried to the stigma of another flower. These devices are so elaborate in many orchids that the m
. Nature and development of plants. Botany. 424 THE ORCHIDALES into a waxy mass, pollinium (pi. pollinia) which is attached to a sticky part of the rostellum (Fig. 293, B,C). The remarkable feature about these gaudy flowers is the relation that the label- lum, anther, rostellum and stigma sustain to each other. The position of these organs is such that an insect visiting the flower touches with some part of his body the sticky part of the rostel- lum and the pollinia are thus made fast to him and carried to the stigma of another flower. These devices are so elaborate in many orchids that the microspores can only reach the stigma through the agency of an insect. In the lower types of orchids, as the moccasin flower (Fig. 292, B), a somewhat different. Fig. 292. A simple type ot the Orchidales: A, the moccasin flower, Cy- pripedium—-l, labellum; p, the two unmodified petals; s, sepals, two being united below the labellum; h, bract, partially concealing the inferior ovary. B, section of the flower—I, labellum; i, stigma; an, anther; st, shield-like sterile stamen covering the two anthers and stigma; 0, ovary; h, bract. arrangement is found. The bee enters the opening in the upper part of the labellum and feeds upon the glands distributed along the bottom. In leaving the flower he forces his way through the small opening on either side of the style and so he first comes into contact with the stigma and later with the anthers, which are two in number and located back of the stigma. In this flower the anthers are surrounded by a sticky mass and the microspores are thus fastened to the insect's body to be carried to another flower. In the higher types of orchids, the insect probing for the nectar touches the sticky discs of the rostellum, to which 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
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisher, booksubjectbotany
