Plate 161.
Reading edition
COTYLEDON ORBICULATA. Cape Province, Transvaal. Crassulaceae. Cotyledon, Linn.; Benth. et Hook. f. Gen. Plant. vol. i. p. 659.
Cotyledon orbiculata, Linn. Sp. Pl. 614; Fl. Cap. vol. ii. p. 371.
Cotyledon orbiculata was first figured in the Botanical Magazine in 1795, and stated to have been introduced into English gardens about the year 1690. The genus Cotyledon differs from Crassula (see Plate 115) by having twice as many stamens as petals. It is a large genus in South Africa, and represented by between 30 to 40 species. Several species of the genus are of economic interest inasmuch as they produce disease in stock. The well-known “Krimptziekte” of goats is caused by C. Wallichii. The Division of Veterinary Education and Research carried out some feeding experiments with C. orbiculata in 1921 at Grahamstown, and definitely proved that feeding the leaves to fowls caused death.
Our plate was prepared from specimens grown at the Division of Botany, Pretoria. The plant goes under the common names of “hondenoor,” “Konterie,” “Varkens ooren,” and “pig’s-ear.”
Description:—Low shrubby somewhat succulent plant. Stem with light-brown bark. Leaves opposite, 6·5 to 8 cm. long, 4 to 4·5 cm. broad, obovate, subacute, glabrous, glaucous, with red margins. Peduncle up to 27 cm. long, 8 mm. in diameter, terete, reddish in colour with a whitish bloom. Inflorescence a panicle of cymes. Calyx-tube almost none; lobes 5 mm. long, ovate, acute. Corolla-tube 2·8 cm. long, 1·5 cm. in diameter; lobes 2 cm. long, 7 mm. broad, oblong, obtuse, slightly twisted counter-clockwise. Stamens 10, five shorter inserted near the base of the corolla-tube, with a ring of hairs at the point of attachment and produced below the hairs into a strong rib; filaments subterete; anthers ovate. Carpels as long as the shorter stamens. Glands forming a deep concave body at the base of each carpel.
Plate 161.—Fig. 1, longitudinal median section of the flower; Fig. 2, gynæcium, showing glands; Fig. 3, stamen; Fig. 4, tuft of hairs on filament; Fig. 5, side view of gland at base of carpel.
F.P.S.A., 1925.
