llow spines, 1/4 in.
long, and a solitary central spine, 1/2 in. in length, and coloured red.
Flowers terminal, just peeping above the tubercles; sepals and petals
acute, yellow, 3/4 in. long; anthers yellow; stigma white. An old garden
plant, introduced from Mexico. It flowers in May and June. For its
cultivation it may be treated as recommended for M. pusilla.

M. villifera (hair-bearing).--Stem similar to the last, but usually
proliferous at the base; tubercles angular, short, woolly in the axils,
and bearing four rigid, short, reddish-brown spines on the apex. Flowers
pale rose, with a line of purple down the middle of each petal; they are
developed near the top of the stem, in May. Native country, Mexico. This
plant thrives if treated as recommended for M. pusilla. There are
several varieties known, distinguished by their paler or darker flowers,
or by a difference in the length and arrangement of the spines.

M. viridis (green).--Stem 4 in. high by 3 in. in diameter, proliferous at
the base; tubercles short, four-angled, crowded in spiral rows, woolly
at the base, bearing each five or six radiating hair-like spines on the
apex, and one central erect one, none more than 1/4 in. long. Flowers
erect, on top of stem, with recurved, pale yellow petals, 1 in., long;
they are produced in May and June. Introduced from Mexico in 1850. It
may be grown in a sunny frame out of doors during summer, and on a dry,
warm greenhouse shelf in winter.

M. vivipara (stem--sprouting).--A tufted, free-growing Thimble Cactus,
producing its small stems in such profusion as to form a cluster as much
as 3 ft. in diameter. The small tubercles are hidden by the numerous
radial spines, which are in clusters of about twenty; they are white,
hair-like, stiff and 1/2 in. long; the central spines, numbering from four
to six, are a little longer. Flowers from apex of stem, 11/2 in. long and
wide, and composed of about thirty fimbriated sepals and twenty-five to
forty narrow petals; colour bright purple. Fruit 1/2 in. long, pale green
when ripe. The flowers, which appear in May and June, usually expand
after mid-day. Native of Louisiana. In the North-West plains and Rocky
Mountains of North America this plant is abundant, often forming wide
cushion-like tufts, which, when covered with numerous purple, star-like
flowers, have a pretty effect. In Utah and New York it is commonly
cultivated as a hardy garden plant, bearing exposure to keen frosts and