This rare and interesting plant was found by Dr. R. Marloth in the Calvinia District. An examination of fresh specimens has enabled us to reduce the three species described in the “Flora Capensis” to a single species, and the genus Daubenya therefore becomes one of South Africa’s monotypic genera. Our conclusions have been confirmed by independent observations made by Dr. Marloth, and we give below the notes he forwarded to the Division of Botany.
“The colour of the flower is the most brilliant scarlet known in the Flora of South Africa, and especially dazzling when seen in full sunlight. This effect is due to the combination of two pigments in the subepidermal tissues of the flower, viz. a granular yellow pigment distributed through all the cells, and a bright red solution present in most of the cells of the subepidermal layer, but absent in others. This peculiarity of structure also explains the occurrence of plants with yellow flowers, for if through some cause or other (as a sport), the red pigment is not produced, the flower is plain yellow, just as in such a case the flower of the red Watsonia (W. rosa) becomes pure white (Arderne’s Watsonia). It so happened that the yellow form was first introduced into England and described by Lindley as Daubenya aurea (1835), hence this name has to be retained for the species, although the flower is generally scarlet, and the yellow form has only arisen as a sport. There is, however, no structural difference between D. aurea Lindl., D. coccinea Harv., and D. fulva Lindl.”
The length of the floral segments and of the peduncle, given as distinguishing characters by Lindley, is very variable in the specimens seen by us (over one hundred); some of them are scarlet, others yellow, and some dull orange. The scent of the flowers is unpleasant, somewhat recalling that of the flowers of Rhus.
The home of this remarkable plant was unknown to botanists until re-discovered in 1920. It grows in heavy red clay soil on the farm Fransplaas, about 40 miles north of Sutherland, and flowers in September.
The genus was named by Dr. Lindley in honour of Dr. Charles Daubeny, Professor of Botany at Oxford, “whose interesting researches in vegetable Chemistry have materially conduced to improve our knowledge of the physiology of plants.”
Specimens are preserved in the National Herbarium, Pretoria (Herb. No. 1458).
Description:—An acaulescent herbaceous plant. Bulb 1·6 cm. long, 1·9 cm. in diameter, covered with brown membranous tunics with numerous fibrous roots from the base. Leaves 2, flat, 5-8 cm. long, 4-5 cm. broad, ovate, subacuminate, obtuse, narrowed and clasping at the base, many-nerved, with margins narrowly membranous. Capitulum about 10-flowered, with a peduncle 3 cm. long, clasped by the leaf base and beneath the soil. Outer bracts white, membranous, 2·7 cm. long, 1·6 cm. broad, oblong; inner bracts 2·5 cm. long, 9 mm. broad, obovate-spathulate, entire, clasping the perianth-tube. Pedicels 5 mm. long, 3 mm. broad, compressed, fleshy. The outer flowers 2-lipped and differently shaped from the inner. Perianth-tube of outer flowers 2 cm. long, 4 mm. in diameter, somewhat compressed; lobes of lower lip 2·6 cm. long; the middle lobe 1·4 cm. broad; the 2 side lobes 1 cm. broad; all obovate-oblong, obtuse; lobes of upper lip 3 mm. long, 1 mm. broad, linear. Perianth-lobes of inner flowers 3-6 mm. long, all linear or lanceolate. Stamens inserted at different levels; filaments 3-6 mm. long, terete, fleshy, tapering upwards; anthers 2 mm. long, oblong. Ovary 7 mm. long, 2·5 mm. in diameter, narrowly ellipsoid, glabrous; style 2·5 cm. long, terete, with 3 minute stigmas at the apex.
Plate 71.—Fig. 1, plant viewed from above; Fig. 2, plant, side view; Fig. 3, a single flower; Fig. 4, side view of flower of outer whorl; Fig. 5, flower from middle of inflorescence; Fig. 6, the same flower viewed from above, showing the stamens and style; Fig. 7, bract.
F.P.S.A., 1922.