w, and forming a large
saucer, in the middle of which the numerous stamens, with yellow
anthers, are arranged in a crown. There is something incongruous in the
tall, spine-clothed, pole-like stem, upon which large, beautiful,
water-lily-like flowers are developed, looking quite out of place on
such a plant. Flowers in spring and early summer. It requires warm
greenhouse or stove treatment. There are some fine examples of this
species at Kew. A variety of this species, with a fasciated or monstrous
habit, is sometimes cultivated. Introduced in 1830.

C. pleiogonus (twisted-angled); Fig. 26.--An erect cylindrical-stemmed
species, from 6 in. to 1 ft. high by 4 in. in diameter, with from ten to
fourteen angles or ridges; these are somewhat tumid, and marked with
depressions, from which the star-like clusters of spines spring, about a
dozen spines in each cluster, the central one much the largest. The
flowers are about 8 in. long, the tube being rather thick and
cylinder-like, expanding at the top, so as to form a sort of cup, in
which the petals are arranged in several rows, with the middle filled by
the numerous stamens, surmounted by the club-like pistil. The colour of
the flowers is purple-red. This species appears to have first found its
way into cultivation through some Continental garden, its native country
being unknown. It thrives only in a warm house, developing its flowers
in summer.

[Illustration: FIG. 26.--CEREUS PLEIOGONUS.]

C. polyacanthus (many-spined).--A newly-introduced species, from El
Paso, in Mexico, where it is common on the sand ridges and stony hills.
Stem 10 in. high, 2 in. to 4 in. wide, pale green or glaucous, with about
eight ridges, the spines being placed along the angles in clusters of
half a dozen or so, and about 1/2 in. apart. The flowers are 2 in. to 3 in.
long; the tube spiny; the petals semi-erect and concave, rounded at the
tip, and forming a shallow cup or wine-glass-like flower; the colour of
the petals is deep blood-red. This beautiful Cactus is exceptional in
the length of time its flowers remain expanded and fresh, lasting a week
or more; and as the plant is very free flowering, there is usually a
beautiful display of rich red blossoms for about six weeks. It may be
grown in a cool greenhouse or window, requiring no artificial heat
beyond what would be necessary to insure its protection from frost. It
flowers in spring.

C. procumbens (trailing); Fig. 27.--This is a very pret