nd flowered in July.

E. cylindraceus (cylindrical).--A large-growing kind, attaining a
height of several feet, very broad, and, as the name denotes,
cylindrical in shape. When large, the stem often develops lateral
branches about its base. Cultivated plants of it are 6 in. high, the
sides marked with about a score of ridges, upon which, arranged in a
dense cluster, are the stout, strong spines, the longest of them 3 in.
long, hooked, and projecting outwards, the shorter spreading and
interlacing so as to form a sort of spiny network all round the stem.
The flowers are yellow, 2 in. long, and are composed of a short, thick
tube bearing from forty to fifty fringed sepals, and about half that
number of petals, which are also fringed. There are as many as a dozen
flowers opened together on stout, aged plants; it is, however, more
because of the densely spinous stems than the flowers that this species
has found its way into cultivation. It cannot be recommended for any
except large collections, and where it can be grown in a stove
temperature. It is a native of the hot deserts of Colorado, and was
introduced about ten years ago. There are several healthy young
specimens of it in the Kew collection.

E. echidne (viper; probably in allusion to the fang-like spines).--This
species is remarkable in having a stout cylindrical stem, 12 in. high by
8 in. wide, with about a dozen deep ridges; these are disposed spirally,
and bear tufts of rigid, broad spines, 1 in. or more long, spreading, so
as to interlace and form a wire-like network all round the stem. It may
be mentioned here that an American naturalist has recently suggested
that the object of these iron-like spines on the stems of many Cactuses,
and more especially on the majority of the Hedgehog kinds, is not so
much to defend the fleshy stems from browsing animals as to afford
protection from the scorching rays of the sun, which would otherwise
cause the stems to blister and shrivel; and the nature of the spiny
covering of E. echidne seems to support such a view. As in many others,
the clusters of spines in this plant have their bases embedded in a tuft
of whitish wool. The flowers are developed near the centre of the top of
the stem, and are of medium size, bright yellow, with whitish stamens;
they are produced two or three together, in summer. This species is a
native of Mexico; it thrives in a greenhouse where frost is excluded,
but only rarely flowers with us under cu