. Beginners botany. Botany. some of the anthers mature simultaneously with the pistils, so that there is chance for self-polhnation in case for- eign pollen does not arrive. Even when the stigma receives pollen from its own ^^^^^^^^^\ 'OV-'^^^^^^^ --^ flower, cross-fer- tilization may result. The hol- lyhock is proter- androus. Fig. 198 shows a flower recentlv Fig. 198. —Flower of Hollyhock; proterandrous. expanded. The centre is occupied by the column of sta- mens. In Fig. 199, showing an older flower, the long styles are conspicuous. Some Jloivcrs arc so constructed as to pivJiibit self-poll
. Beginners botany. Botany. some of the anthers mature simultaneously with the pistils, so that there is chance for self-polhnation in case for- eign pollen does not arrive. Even when the stigma receives pollen from its own ^^^^^^^^^\ 'OV-'^^^^^^^ --^ flower, cross-fer- tilization may result. The hol- lyhock is proter- androus. Fig. 198 shows a flower recentlv Fig. 198. —Flower of Hollyhock; proterandrous. expanded. The centre is occupied by the column of sta- mens. In Fig. 199, showing an older flower, the long styles are conspicuous. Some Jloivcrs arc so constructed as to pivJiibit self-polli- nation. Very irregular flowers are usually of this kind. With some of them, the petals form a sac to inclose the anthers and the pol- len cannot be shed on the stigma but is retained until a bee forces the sac open; the pollen is rubbed on the hairs of the bee and transported. Fig. 199. —Older Flower OF Hollyhock. t, , a Regular rlowers usu- ally depend mostly on dichogamy and the selective power of the pistil to insure crossing Flowers that are very. 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. Toronto : Macmillan
Size: 1743px × 1434px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectbotany, bookyear1921
