. Essentials of botany. Botany; Botany. 172 ESSENTIALS OF BOTANY 204. Nectar Guides. — In a large number of cases the petals of flowers show decided stripes or rows of spots of a color different from that of most of the petal. These commonly lead toward the nectaries, and it is possible that such markings point out to insect visitors the way to the nectaries. Following this course, the insect not only secures the nectar which he seeks, but probably leaves pollen on the stigma and becomes dusted with new pollen, which he carries to another flower. 205. Facilities for Insect Visits. — Regular po
. Essentials of botany. Botany; Botany. 172 ESSENTIALS OF BOTANY 204. Nectar Guides. — In a large number of cases the petals of flowers show decided stripes or rows of spots of a color different from that of most of the petal. These commonly lead toward the nectaries, and it is possible that such markings point out to insect visitors the way to the nectaries. Following this course, the insect not only secures the nectar which he seeks, but probably leaves pollen on the stigma and becomes dusted with new pollen, which he carries to another flower. 205. Facilities for Insect Visits. — Regular polypetalous flowers have no special adaptations to make them singly accessible to insects, but they lie open to all comers. Bisexual flowers probably always are more or less adapted to partic- ular insect (or other) visitors. The adaptations are extremely numer- ous; here only a very few of the simpler ones will be pointed out.' Where there is a drooping lower petal (or, in the case of a gamopetalous corolla, a lower lip), this serves as a perch upon which flying insects may alight and stand while they explore the flower, as the beetle is doing in Pig. 128. In Fig. 129 one bumblebee stands with her legs partially encircling the lower lip of the dead-nettle flower, while another perches on the sort of grating made by the stamens of the horse-chestnut flower. The honey-bee entering the violet chngs to the beautifully bearded portion of the two lateral petals while it sucks the nectar from the spur beneath. 1 See Knuth-Davis' Handbook of Flower Pig. 128. A Beetle on the Flower of the Twayblade. (Enlarged three times.). 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 Bergen, Joseph Y. (Joseph Young), 1851-1917. Boston, Ginn
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