The Craterostigma figured on the accompanying plate is known from various localities in the Transvaal. It is also recorded from the neighbourhood of Bulawayo in Rhodesia and from other parts of tropical Africa reaching as far north as Arabia and Abyssinia. The genus is mainly a tropical one, and is represented by about a dozen species, three of which are found in South Africa.
C. plantagineum is a charming little plant which would be well worth cultivation in the greenhouse and should be easily grown. Our plate was prepared from specimens collected by Dr. I. B. Pole Evans, C.M.G., on the portion of the farm Rietfontein 448, near Pretoria, belonging to Mr. J. F. Ludorf. The plants were found growing in great profusion in shallow soil not more than one inch deep on a large quartzite outcrop. They were in flower during November and December.
Description:—An acaulescent plant with a rosette of radical leaves. Leaves 6-6·5 cm. long, 3-3·5 cm. broad (the inner smaller), ovate, obtuse, narrowed at the base, with crenulate, ciliated margins and with the nerves depressed above, prominent beneath, glabrous above, pubescent beneath, especially on the veins. Peduncles 3 or more to a plant, 3·5-4 cm. long, terete, pubescent, bearing about 8 opposite flowers in a raceme. Bracts 1 cm. long, 5 mm. broad, ovate-lanceolate, acute, slightly connate at the base, glabrous except on the keel, ciliate. Pedicel 7 mm. long, flat on the upper surface, convex on the lower surface, pubescent, ciliate. Calyx-tube 4·5 mm. long, 2·5 mm. in diameter, deeply fluted, pubescent; lobes 1 mm. long, ovate, sub-acute, ciliated. Corolla 2-lipped; tube 7 mm. long, tubular; lower lip 9 mm. long, 1 cm. broad, 3-lobed, with the lobes obovate, crenulate; upper lip 7 mm. long, oblong-ovate, bilobed at the apex. Stamens of two different kinds; those attached to the lower lip with filaments 7 mm. long, bent at right angles below and then swollen to form two callosities on the lip; those attached to the upper lip 2 mm. long; anther cells diverging, those of each pair of stamens joined. Ovary 2 mm. long, 1·25 mm. in diameter, ovoid; style 8 mm. long, terete, gradually widening above, glabrous; stigma bilobed, with the lobes broadly ovate and somewhat membranous. (National Herb. Pretoria, No. 2644.)
[Plate 106.]—Fig. 1, median longitudinal section of flower; 2, front view of flower enlarged; 3, bract; 4, calyx; 5, stamens; 6, pistil; 7, lower portion of under surface of leaf; 8, section of pedicel snowing convex and flat surfaces.
F.P.S.A., 1923.
