bout 1850; it thrives only when
grown in a warm greenhouse, where the temperature in summer may be
allowed to run up to 90 degs. with sun heat. For large collections it is
one of the most desirable.

[Illustration: FIG. 39.--PORTION OF PLANT OF ECHINOCACTUS
LONGIHAMATUS.]

E. Mackieanus (Mackie's); Bot. Mag. 3561.--A small plant, not more than
about 5 in. high, and 2 in. broad at the base, widening slightly upwards.
The ridges are broken up into numerous fleshy, rounded, green tubercles,
crowned with a tuft of thin brown spines from 1/2 in. to 1 in. long, their
bases set in a small pad of yellow wool: As the stem gets older, it
loses its tubercles at the base, which are changed into brown wrinkles.
The flowers are developed on the top of the stem, generally two or three
together, egg-shaped and scaly when in bud, 21/2 in. across when expanded;
the petals white, tipped with brown; the stigma green, club-shaped. This
curious little Cactus is one of about a dozen species found in the
Chilian Andes. It was introduced in 1837 by the gentleman whose name it
bears, and who, at that time, possessed a famous collection of Cacti.
Like the rest of the Chilian kinds, it should be cultivated in a cool
greenhouse in full sunshine, where it will produce its flowers in
summer.

E. mamillarioides (Mamillaria-like); Bot. Mag. 3558.--This is another
small, tubercled species, which, like the preceding, is a native of
Chili. Its stem is very irregular in form, owing to the crowding of the
tubercles, which look as if they were filled with water. The spines are
small, in tufts of about half a dozen, set in a little cushion of
yellowish wool. In size, the whole plant is like E. Mackieanus, but it
blossoms more freely, as many as sixteen flowers having been borne at
one time by a plant at Kew. These were short-tubed, the calyx clothed
with green scales, and the petals 2 in. long, recurved at the apex,
forming a beautiful cup-like flower of a bright yellow colour, with a
band of red down the centre of each petal; the stamens and pistil
yellow. The number of flowers developed on the small stem formed by this
plant is quite extraordinary. It grows and flowers freely in an ordinary
greenhouse, and would thrive in a sunny window if kept dry during the
winter.

E. mamillosus (nipple-bearing).--A short, dumpy plant, with numerous
tubercled ridges, bearing bunches of dark brown hair-like spines, which
form a close network about the stem. The flowe