Plate 155.
ALOE PETRICOLA.
Transvaal.
Liliaceae. Tribe Aloineae.
Aloe, Linn.; Benth. et Hook. f. Gen. Plant. vol. iii. p. 776.
Aloe petricola, Pole Evans in Trans. Roy. Soc. S. Afr. vol. v. p. 707.
This Aloe was first collected and photographed by Dr. Pole Evans at Nelspruit in September 1905. In the Nelspruit Valley (Barberton District) the plant is found chiefly on the granite outcrops, and in similar localities at Eland’s Hoek and in the Kaap Valley, where it was collected by Mr. Geo. Thorncroft. Like most of our Transvaal aloes, it flowers in mid-winter (July), and the flowering period extends well into August. Aloe petricola is one of the stemless species, and the bicoloured inflorescence makes it quite a striking plant in the rockery. In the oldest flowers the filaments contract within the perianth, and the style then becomes exserted.
Our plate was prepared from specimens which flowered at the Division of Botany, Pretoria.
Description:—Leaves 34 cm. long, 8 cm. broad at the base, lanceolate, acuminate, ending in a short spine, concave on the upper surface, convex on the lower, with spines along the margins and 1 to 3 spines on the back near the apex; spines about ·2 mm. long and 1·5 cm. apart. Inflorescence forked; peduncle bearing the inflorescence about 20 cm. long, 1·2 cm. in diameter, terete, bearing ovate acuminate membranous bracts; flowers in a dense spike about 21 cm. long, 6 cm. in diameter, all reflexed, at first red, later becoming greenish-white, with dark green bands. Floral bracts membranous, reflexed, 1·5 cm. long, 5 mm. broad at the base, ovate, cuspidate, 5-nerved. Outer perianth-segments 2·5 cm. long, 6 mm. broad, lanceolate, obtuse, distinctly 3-nerved (faintly 5-nerved); inner segments 2·3 cm. long, 9 mm. broad, somewhat keeled, 3-nerved. Filaments 2·5 cm. long, broadest in the[{144}] middle and tapering to the base and apex, dark purple above, greenish-white below; anthers 3 mm. long with dark yellow pollen. Ovary 5 mm. long, cylindric; style 2 cm. long, cylindric; stigma minute.