. Notes on the life history of British flowering plants. Botany; Plant ecology. 310 BRITISH FLOWERING PLANTS SCROPHULARIA Protogynous wasp flowers. Nectar secreted by a ring at the base of the open corolla. Cleistogamous flowers also occur. There are four British species. Two have the leaves glabrous; in two they are downy. Of the former, S. aquatica has the stem four-winged; in S. nodosa it is four-angled, but not winged. Of the downy-leaved species, S. Scorodonia has purple flowers, S. vernalis yellow. One of the stamens is barren, and usually forms a scale under the upper lip. The reason or
. Notes on the life history of British flowering plants. Botany; Plant ecology. 310 BRITISH FLOWERING PLANTS SCROPHULARIA Protogynous wasp flowers. Nectar secreted by a ring at the base of the open corolla. Cleistogamous flowers also occur. There are four British species. Two have the leaves glabrous; in two they are downy. Of the former, S. aquatica has the stem four-winged; in S. nodosa it is four-angled, but not winged. Of the downy-leaved species, S. Scorodonia has purple flowers, S. vernalis yellow. One of the stamens is barren, and usually forms a scale under the upper lip. The reason or use of this peculiar arrangement is not known. S. nodosa (Figwort).—-The flowers are small (Fig. 198) and generally reddish brown, which seems to be a favourite colour with wasps. The tube of the corolla is a pale greenish purple. The flower has a scent, pleasant no doubt to wasps, but disagreeable to us. In the first stage of the flower, which lasts two days, the stigma projects, and the anthers are not ripe; in the second, which also lasts two days, they open and expose the pollen. The stigma and anthers lie on the lower side of the flower, and the upper (fifth) stamen being use- less, the anther is not developed, but forms a widened end to the stamen. This, however, is so well formed that I cannot help suspecting it has some function which has not yet been observed. The style, after ferti- lisation, gradually curves down.^ In bee flowers the lower blossoms generally open first, and bees begin below and work their way up. Wasps, on the contrary, begin at the top. The flowers open irregularly, but the general result is that the younger flowers are fertilised with ^ T. W. Fulton "On Soropliularia," Trans. Bot. Soc. Edinb. xvi. (1886).. Fig. 198.—Scrophularia 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 resembl
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