. Notes on the life history of British flowering plants. Botany; Plant ecology. 306 BRITISH FLOWERING PLANTS. Fio. 197 mgrum. We have six species. V. Thapsus may be recognised at once hj its decurrent leaves ; two are nearly glabrous or slightly glandular-hairy— V. Blattaria, with pedicels mostly longer, V. virgatum shorter, than the calyx. Of the other three, V. nigrum has the leaves cordate, the others narrow at the base ; of these, V. Lychnitis has white flowers ; V. pulverulentum, yellow. Crosses are not infrequent in this genus. Gaertner found that taking the produce of V. Lych- nitis wit
. Notes on the life history of British flowering plants. Botany; Plant ecology. 306 BRITISH FLOWERING PLANTS. Fio. 197 mgrum. We have six species. V. Thapsus may be recognised at once hj its decurrent leaves ; two are nearly glabrous or slightly glandular-hairy— V. Blattaria, with pedicels mostly longer, V. virgatum shorter, than the calyx. Of the other three, V. nigrum has the leaves cordate, the others narrow at the base ; of these, V. Lychnitis has white flowers ; V. pulverulentum, yellow. Crosses are not infrequent in this genus. Gaertner found that taking the produce of V. Lych- nitis with pollen of its own species as 100 seeds, when ferti- lised with pollen from V. phoeni- ceum it produced 90 seeds, with that of V. nigrum 63, of V. Blat- taria 62. On the other hand, the ovary is quite sterile to pollen of the same flower.^ Kerner calls attention to the beautiful manner in which the rain is collected and carried down to the roots. The upper part of the leaves hangs downwards, and consequently the rain drops off at the tip. But as the leaves are shorter the higher their position on the stem, the drops fall on that part of a lower leaf which shelves towards the stem. Thus all the rain-water received by the plant is eventually conducted to the tap-root. V. Thapsus.—Two of the stamens are longer than the other three, which have hairy filaments. The leaves have stomata on both sides, and a hairy covering which it is impossible to wet. The whole plant is tomentose. V. Blattaria.—The flowers are homogamous, gener- ally yellow, but sometimes white. According to Kerner the corolla secretes nectar, but this is denied by Kirchner. The pistil projects beyond the anthers. Eventually the corolla drops ofi" and slips down the ^ Darwin, Forms of 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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