Pereskia zehntneri sp nov

Shrub, 2 to 3 meters high, with a central erect trunk, very spiny; branches numerous, horizontal, usually in whorls, sometimes as many as 10 in a whorl; branches terete, green, fleshy, very easily detached from the stem; leaves stiff, fleshy, numerous, small, 2 to 4 cm. long, ovate to orbicular, acute, standing at right angles to the branches; areoles large, filled with short white wool and numerous slender white spines; flowers at tops of branches, large, 7 to 8 cm. broad, bright red, appearing in November; petals broad, retuse; ovary borne in the upper end of the branch, very narrow, 3 to 4 cm. long, bearing the usual leaves, areoles, and spines of the branches.

Collected by Dr. Leo Zehntner (Nos. 567 and 630, type) November 15 and 16, 1912, at Born Jesus da Lapa, Bahia, Brazil, on the Rio Sao Francisco.

This is a very rare plant and seen in only one locality, in soil of a peculiar chalky formation. Living plants were taken by Dr. Zehntner to the Horto Florestal, Joazeiro, Brazil, where they grew well, and whence Dr. Rose obtained specimens in 1915 which were shipped to the United States under No. 19722.

The plant is known in Bahia under the name quiabento. It is probably not a true Pereskia; it suggests in its habit and foliage some of the Mexican species of Pereskiopsis, but it may represent a distinct genus.

Text-figures 6 and 7 are from the type plant above cited.

6. Pereskia sacharosa Grisebach, Abh. Ges. Wiss. Gottin gen 24: 141. 1879.

Pereskia amapola Weber, Dict. Hort. Bois 938. 1898.

Pereskia argentina Weber, Dict. Hort. Bois 938. 1898.

Small tree or shrub, 6 to 8 meters high; branches green and smooth, but in age becoming yellowish or light brown; leaves lanceolate to oblanceolate, 8 to 12 cm. long, cuneate at base, more or less pointed at apex; young areole with 1 to 3 spines, the longest 5 cm. long, the others when present not over half as long, all acicular and dark in age; older areoles often with 6 or more spines; pedicels sometimes 10 mm. long; flowers in terminal clusters, either white or rose-colored and very showy, 8 cm. broad, open at midday; sepals about 8, 1 or 2 petal-like, the others scale-like, the outer sepals and upper scales bearing long hairs; petals 8, rose-colored, ob-lanceolate, 3 cm. long; stamens free from the petals, numerous, unequal, erect; filaments, style, and stigma-lobes white; ovules borne on the lower part of ovary; ovary bearing small leaves, their axils filled with short wool and occasionally bearing a spine; fruit hard, 2.5 to 4 cm. in diameter, more or less tapering at base, many-seeded, leafless or nearly so, sometimes proliferous.

Type locality: Cobos, Oran, Argentina.

Distribution: Paraguay and Argentina.

Schumann (Gesamtb. Kakteen 765. 1898) gives Opuntia sacharosa Grisebach as a synonym of this species, but erroneously, since it was never taken up by Grisebach as an Opuntia. The Index Kewensis refers this species to P. aculeata, doubtless following Hooker's references in Curtis's Botanical Magazine for 1890 in regard to Argentine plants, which even then were little known.

The common name of this plant in Argentina is sacharosa. It is sometimes used as a hedge plant.

Plate 11, figure 4, represents a leafy branch of a plant given to the New York Botanical Garden by Frank Weinberg in 1903; figure 5 shows its fruit.

Fig. 7.—Pereskia zehntneri. Photograph by Paul G. Russell.

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